Loss of oil pressure during vtech operation.

[nsxspdfreak]

I am having a problem with the front bank vtec kicking out due to low oil pressure and getting a CEL 22 code (Front Vtec Oil Press Switch).

First some history on the car. The car is basically stock. I purchased the car this past Feb with 54k miles on it. From 2001 to June 2014 the car had only been driven maybe 6-7k miles and spent most of it's time in storage container until it was sold in June 2014 to the guy I purchased it from. When I bought the car it was still on the original timing belt so I had immediately put the car into the shop for extensive maintenance. After I got the car back I still had to replace the exhaust system and radiator and do some suspension work so the car was only occasionally driven. During a dyno run I did prior to installing the new headers and exhaust we found that the car was not putting out the HP it should have been putting out. After doing a lot of investigating we found that the new timing belt had jumped a tooth. At this point I decided to pull the motor to retime it and replace the LMA's. During the process is when I found that one front intake cam journal was wiped out. This then led to installing a new front head/cams/rockers. In the process Cometic head gaskets and all new seals and orings were installed. The oil was also changed from what had been 10/40 syn blend that the previous owner had been using to 10/30 Penzoil Utra Syn. The reason for why the journal wiped out is up for debate, but not part of this discussion. Prior to this I was not having any issues with the Vtec that I knew of, but the car was also not driven hard between the time I purchased it and when I found the bad bearing.

I've already eliminated the pressure switch as being the problem, so I now needed to test the system by a process of elimination. First was to do a high rpm test run while keeping a close eye on oil pressure. As RPMS increased into Vtec range I could hear and feel the Vtec come on, but as it did oil pressure dropped from 4.5-5 down to less than 1. Simultaneously the CEL light came (later determined to be a code 22). When this happened I immediately backed off of the throttle, and watched the oil pressure come back up to above 4. I then repeated the run and watched the same thing happen again. This is the first time I've seen this happen, but it's also the first time that I paid close attention to the oil pressure gauge while in vtec rpm range. On this car oil pressure runs anywhere from 1-2 at an idle and 4-4.5 at 3000-4500 rpms, which is normal. Since I just replaced the front cylinder head I was thinking that the oring seal on the vtec oil passage way fell out of position during reassembly and the oil for the vtec is just dumping without any restriction into top of the head, hence the low oil pressure after the valve is opened. To eliminate this possibility I first disconnected both Vtec solenoids and then did another high rpm run. This time pressure actually climbed to above 6 as rpm climbed, which was to be expected with no vtec operating to bleed down the pressure. Next I reconnected only the rear bank solenoid and repeated the run. This time oil pressure remained stable at about 4-4.5 throughout the rpm range including into vtec. I then disconnected the rear solenoid and reconnected the front, and repeated the run again. Again oil pressure remained stable, as it did with the rear bank, with oil pressure remaining at approximately 4.5. There was no severe oil pressure drop like I had with both vtecs engaged simultaneously.

It would appear that the oil pump can't keep up with the demand of both front and rear vtecs running simultaneously, and when the valves open pressure drops dramatically causing the ECM to sense low vtec oil pressure. What doesn't make sense is why am I getting only a code 22 for the front bank and not a 52 for the rear bank. I would think that if one cuts out due to low oil pressure (as indicated on the instrument panel gauge) the other should.

I've put close to 1000 miles on it since the head change and it doesn't appear that I have burned any oil, and there is no indication in the exhaust that I'm burning oil.
One thing to note is that when I purchased the car in Feb the previous owner was using 10/40 syn blend oil and I changed it to 10/30 following the head replacement. There is a remote possibility that the 40 wt oil he was using was masking an oil pressure issue and may have been raising pressure just enough to keep the Vtec engaged. It also may have contributed to the cam bearing failure.

 

[RYU]

I'd try different oil weights for testing purposes only. I think seeing one of the CEL for the first solenoid makes sense. The computer probably just registers the first one but i'm not 100% sure.

My *guess* is you might have a worn out oil gear and oil pump housing and it's not able to build enough pressure anymore. It's a pure guess since you've been very thorough in your testing thus far - kudos to you on that. Keep us posted.

Also read posts from [MENTION=25108]illwillem[/MENTION]. Unfortunately he's had his fair share of crappy vtec solenoid issues

 

[Larry Bastanza]

Guys,

First off I want to say this is purely speculative. But on the cylinder block, one for each head there is an item called an "Oil Control Orifice"

Go here: http://www.acuraautomotiveparts.org...omp=List All&vinnoT=&trim=&trans=&view=normal

Items #3 and #4 . This Orifices actually "pinch" the oil passage and if used on the input side of a pressure source will lower pressure, however best I can tell these are used to pinch the return oil passage from the VTEC oil circuit, which would make sure you have enough residual pressure to operate the VTEC system when the VTEC selonoid opens. If by chance the engine was assembled and one of these was omitted, this could be why when the VTEC engages on that cylinder head, the pressure drops too far. I am ranked this a 50/50 comment, since the oil system schematic does not 100% state this, I am going by looking at the drawing of the VTEC oil circuit.

I comment on this because after a few rebuilds myself, I noticed these parts, and that they truly "pinch" the oil passage.

My $.02

Regards,
LarryB

 

[nsxspdfreak]

Yeah, I'm all for checking out the most obvious and simplest things first when it comes to diagnosing problems. I wouldn't be surprised if the 40w oil was masking the problem just enough to keep vtech oil pressure in spec. I've also noticed during the process that the computer does indeed pickup certain faults and then not other subsequent faults. When I disconnected both pressure switches simultaneously it picked up the front bank error 22, but not the rear bank 52. I'll be keeping everyone posted and thanks for the input. I'll check out the link you sent me too.
Joe

 

[illwillem]

So i had the EXACT same problem after blowing an oil gear on track. I changed the crank bearings, oil pump, oil gear housing, shimmed the oil gear, swapped vtec solenoids front to rear, got BOTH new solenoids, changed oil weight, went through the harness for faults, got a totally fresh tune, removed shift light removed the accusump... Basically did everything I could thing of but would get the code 22 fault when on track. (strangely it never happened on the dyno) In the end it turned out that I had apparently damaged my crank when i scoured the bearing after blowing the oil gear. I had never even thought to check this, the scoured bearings that came out were barely rubbed and the crank looked good visually, plus the only way to get the crank measured is to drop the motor and remove it..

Long story short- after all that trouble shooting and about two years of track driving with no vtec i just broke down and bought a new long block so i could be done with the issues. Post mortem on the dead motor suggests that the bad crank chewed up the new bearings and clogged or out spec'ed the tolerances on the oil orifices that coincidentally went to the front bank where i was throwing the code. This means that it would initially get to vtec but not be able to sustain prolonged pressures and throw the fault code after dropping out of pressure spec when up in the revs.

Hopefully you can sort your issues out. Good luck.

 

[Mac Attack]

The reason for why the journal wiped out is up for debate, but not part of this discussion.

It's completely relevant to this discussion. If debris caused the wiped cam journal, which may have created more aluminum debris, then you have crap that made it through your filtered engine and could wind up causing problems with the oil pump discharge valve sticking open, getting caught in other bearings, or getting stuck in the oil supply passage orifices between the block and the heads. It could cause scoring in your soft aluminum oil pump housing, or hang up in your (most likely) crudded-up oil cooler.

If it were my engine and I observed scoring like that, I would have stripped the engine, cleaned the passageways, inspected the oil pump, flushed the oil cooler, etc.

Sorry.

 

[nsxspdfreak]

Guys,

First off I want to say this is purely speculative. But on the cylinder block, one for each head there is an item called an "Oil Control Orifice"

Go here: http://www.acuraautomotiveparts.org...omp=List All&vinnoT=&trim=&trans=&view=normal

Items #3 and #4 . This Orifices actually "pinch" the oil passage and if used on the input side of a pressure source will lower pressure, however best I can tell these are used to pinch the return oil passage from the VTEC oil circuit, which would make sure you have enough residual pressure to operate the VTEC system when the VTEC selonoid opens. If by chance the engine was assembled and one of these was omitted, this could be why when the VTEC engages on that cylinder head, the pressure drops too far. I am ranked this a 50/50 comment, since the oil system schematic does not 100% state this, I am going by looking at the drawing of the VTEC oil circuit.

I comment on this because after a few rebuilds myself, I noticed these parts, and that they truly "pinch" the oil passage.

My $.02

Regards,
LarryB

Thanks for your input Larry. I was very methodical when it came to reassembling the heads, especially when it came to the orifices and new orings, but as I'm sure you know as time passes you begin to question yourself did you or didn't you. I took a gazillion photos during disassembly, but not during the reassembly. Wish I had. If you find a drawing of the Vtec oil circuit let me know! I've been looking for one and so far haven't had any success.
Joe

- - - Updated - - -

I'd try different oil weights for testing purposes only. I think seeing one of the CEL for the first solenoid makes sense. The computer probably just registers the first one but i'm not 100% sure.

My *guess* is you might have a worn out oil gear and oil pump housing and it's not able to build enough pressure anymore. It's a pure guess since you've been very thorough in your testing thus far - kudos to you on that. Keep us posted.

Also read posts from @illwillem. Unfortunately he's had his fair share of crappy vtec solenoid issues

Thank for the input Ryu!

Yeah, I'm all for checking out the most obvious and simplest things first when it comes to diagnosing problems. I wouldn't be surprised if the 40w oil was masking the problem just enough to keep vtech oil pressure in spec. I've also noticed during the process that the computer does indeed pickup certain faults and then not other subsequent faults. When I disconnected both pressure switches simultaneously it picked up the front bank error 22, but not the rear bank 52. I'll be keeping everyone posted and thanks for the input. I'll check out the link you sent me too.
Joe

- - - Updated - - -

So i had the EXACT same problem after blowing an oil gear on track. I changed the crank bearings, oil pump, oil gear housing, shimmed the oil gear, swapped vtec solenoids front to rear, got BOTH new solenoids, changed oil weight, went through the harness for faults, got a totally fresh tune, removed shift light removed the accusump... Basically did everything I could thing of but would get the code 22 fault when on track. (strangely it never happened on the dyno) In the end it turned out that I had apparently damaged my crank when i scoured the bearing after blowing the oil gear. I had never even thought to check this, the scoured bearings that came out were barely rubbed and the crank looked good visually, plus the only way to get the crank measured is to drop the motor and remove it..

Long story short- after all that trouble shooting and about two years of track driving with no vtec i just broke down and bought a new long block so i could be done with the issues. Post mortem on the dead motor suggests that the bad crank chewed up the new bearings and clogged or out spec'ed the tolerances on the oil orifices that coincidentally went to the front bank where i was throwing the code. This means that it would initially get to vtec but not be able to sustain prolonged pressures and throw the fault code after dropping out of pressure spec when up in the revs.

Hopefully you can sort your issues out. Good luck.

Thanks for you input illWillem. I'm aware what happens with bad crank bearings so I'm putting that last on the list and keeping my fingers crossed that's not the problem. Two things in favor of not having a bad crank is that I didn't have the problem before I replaced the head and my pressure was pretty good without vtec at high rpms (over 90psi). But, you never know.

- - - Updated - - -

It's completely relevant to this discussion. If debris caused the wiped cam journal, which may have created more aluminum debris, then you have crap that made it through your filtered engine and could wind up causing problems with the oil pump discharge valve sticking open, getting caught in other bearings, or getting stuck in the oil supply passage orifices between the block and the heads. It could cause scoring in your soft aluminum oil pump housing, or hang up in your (most likely) crudded-up oil cooler.

If it were my engine and I observed scoring like that, I would have stripped the engine, cleaned the passageways, inspected the oil pump, flushed the oil cooler, etc.

Sorry.

That is another possibility that I have to take into consideration and something I just may end up having to do. Unfortunately I took the car to the other coast of FL to a DYI shop to install headers and an exhaust system, and do before and after dyno runs. I wasn't planning on spending the next weeks with it stuck on a lift while I traveled back and forth on weekends to get it back together. Time on the lift was costing me money. The thing is that pressure at high rpm without vtec is over 90psi. It's only with Vtec engaged at high rpm where it bleeds off. This was also not a problem I was having prior to discovering the wiped out cam and even on numerous dyno runs made earlier on the same day I found the bad cam. It happened immediately after reassembly. I took it for a quick test drive and immediately returned to the shop where we put it back on the dyno. On the dyno is where the fault first appeared.
Thanks for your input and I'll keep you posted
Joe

 

[Mac Attack]

Is the shop that did the head replacement the one that installed the TB one tooth off (or, where it "jumped")?

 

[nsxspdfreak]

Is the shop that did the head replacement the one that installed the TB one tooth off (or, where it "jumped")?

I had a shop do the TB. I replaced the head. Before I knew about the cam journal I had blamed the shop for the misaligned TB. They had offered to pickup the car and fix the belt, but they were going to do it with the motor in. I wanted to replace the LMA's and cam plugs and seals so I decided to pull the motor myself to make sure it was done correctly. It was during the cam removal that discovered the journal and realized that it was possible that the belt jumped due to the drag on the cam. Unfortunately there is no way of knowing when the journal failed. I'm glad I found it and not the shop. If they had found it the repair would have cost over $10k, and that wasn't going to happen. Either way there's no more bringing a car to a shop for anything other than an alignment.

 

[Mac Attack]

Sorry to hear about that.

It seems unlikely that it is the orifice in the block going to the front head that suddenly became plugged then during the front head replacement.

IIRC, there are only three orings per head. One each for the rocker shafts and one for the cam cap supply side. Other than forgetting to insert a rocker or torque down the cam caps, you shouldn't have any significant bypass path. I assume you used the cams from the replacement head? If not, did you measure the cam clearances per the SM?

Admittedly, I didn't bother in my rebuild since my cams and journals looked great. However, I did have quite a few extra orings with the Honda bottom and top rebuild kit!

Edit....
I reread your posts. If it only happens with vtec engaged, there is a chance you reassembled one of the rocker assemblies without the vtec locking pin.

 

[nsxspdfreak]

Sorry to hear about that.

It seems unlikely that it is the orifice in the block going to the front head that suddenly became plugged then during the front head replacement.

IIRC, there are only three orings per head. One each for the rocker shafts and one for the cam cap supply side. Other than forgetting to insert a rocker or torque down the cam caps, you shouldn't have any significant bypass path. I assume you used the cams from the replacement head? If not, did you measure the cam clearances per the SM?

Admittedly, I didn't bother in my rebuild since my cams and journals looked great. However, I did have quite a few extra orings with the Honda bottom and top rebuild kit!

Edit....
I reread your posts. If it only happens with vtec engaged, there is a chance you reassembled one of the rocker assemblies without the vtec locking pin.

I would like to think that it is a self-inflicted condition from something that was missed on re-assembly, but what has me questioning that is the fact that with either bank's vtec engaged by itself the oil pressure only drops about one tick on the gauge (14psi) compared to dropping from 5 to under 1 with both engaged. This weekend I'll change out the 10/30 oil with 10/40 to see if what effect it has. If it has no affect than it's most likely something missed in reassembly. If it keeps the pressure up enough to keep vtech engaged than I might be looking at a oil pump problem. Either way I still plan on inspecting the orifice seals on the new head. The other head was only removed to replace the head gasket and the cam wasn't touched.

 

[Mac Attack]

I would like to think that it is a self-inflicted condition from something that was missed on re-assembly, but what has me questioning that is the fact that with either bank's vtec engaged by itself the oil pressure only drops about one tick on the gauge (14psi) compared to dropping from 5 to under 1 with both engaged. This weekend I'll change out the 10/30 oil with 10/40 to see if what effect it has. If it has no affect than it's most likely something missed in reassembly. If it keeps the pressure up enough to keep vtech engaged than I might be looking at a oil pump problem. Either way I still plan on inspecting the orifice seals on the new head. The other head was only removed to replace the head gasket and the cam wasn't touched.

Right, since both heads were removed, the same mistake could have been repeated for both heads (missing O-rings in the rocker shaft oil supplies or the o-ring supplying the cam caps). It doesn't seem likely that the orifices in the top of the block were removed as part of the front head replacement or the rear bank HG change... therefore their O-rings shouldn't have catastrophically failed upon head reassembly. Same thing with the oil pump degrading, the pump bypass spring suddenly relaxing, or the oil pump pickup cracking, the pickup screen clogging, or the pickup o-ring suddenly degrading where it mates on the oil pump suction.

Your oil pressure sender on the front head appears to be in better condition than most of our older ones and is giving you meaningful, repetitive results that correlate to the separate oil pressure switch for VTEC. I would not try to mask low oil pressure to the heads with thicker oil since you appear to have an oil supply problem and will have a repeat condition of another camshaft journal getting messed up (or worse).

Before taking the engine apart, I would hook up an electronic (or mechanical but take video where you can see it) oil pressure sender directly to your pump discharge and see it it's a problem with your pump or not during sustained engine speeds over 6k RPM.

Good luck.

 

[nsxspdfreak]

Right, since both heads were removed, the same mistake could have been repeated for both heads (missing O-rings in the rocker shaft oil supplies or the o-ring supplying the cam caps). It doesn't seem likely that the orifices in the top of the block were removed as part of the front head replacement or the rear bank HG change... therefore their O-rings shouldn't have catastrophically failed upon head reassembly. Same thing with the oil pump degrading, the pump bypass spring suddenly relaxing, or the oil pump pickup cracking, the pickup screen clogging, or the pickup o-ring suddenly degrading where it mates on the oil pump suction.

Your oil pressure sender on the front head appears to be in better condition than most of our older ones and is giving you meaningful, repetitive results that correlate to the separate oil pressure switch for VTEC. I would not try to mask low oil pressure to the heads with thicker oil since you appear to have an oil supply problem and will have a repeat condition of another camshaft journal getting messed up.

Before taking the engine apart, I would hook up an electronic (or mechanical but take video where you can see it) oil pressure sender directly to your pump discharge and see it it's a problem with your pump or not during sustained engine speeds over 6k RPM.

Good luck.

Good advice. Thanks

- - - Updated - - -

Right, since both heads were removed, the same mistake could have been repeated for both heads (missing O-rings in the rocker shaft oil supplies or the o-ring supplying the cam caps). It doesn't seem likely that the orifices in the top of the block were removed as part of the front head replacement or the rear bank HG change... therefore their O-rings shouldn't have catastrophically failed upon head reassembly. Same thing with the oil pump degrading, the pump bypass spring suddenly relaxing, or the oil pump pickup cracking, the pickup screen clogging, or the pickup o-ring suddenly degrading where it mates on the oil pump suction.

Your oil pressure sender on the front head appears to be in better condition than most of our older ones and is giving you meaningful, repetitive results that correlate to the separate oil pressure switch for VTEC. I would not try to mask low oil pressure to the heads with thicker oil since you appear to have an oil supply problem and will have a repeat condition of another camshaft journal getting messed up (or worse).

Before taking the engine apart, I would hook up an electronic (or mechanical but take video where you can see it) oil pressure sender directly to your pump discharge and see it it's a problem with your pump or not during sustained engine speeds over 6k RPM.

Good luck.

Looking back at my parts orders I see that I didn't order the o-rings for the two orifices between the block and heads, which means I never removed the orifices or replaced replaced the orings.

 

[nsxspdfreak]

Update on low oil pressure. For the hell of it I drained the 10/30 oil and replaced it with 10/40. No change. After vtec kicks (can hear it and feel it) and continuing acceleration at about 6500 is when the oil pressure starts to drop down to the single tick mark or lower. By backing off the throttle a bit I can keep pressure up enough so the Vtec oil pressure SW doesn't sense low pressure. It takes the pressure to drop below the first tick mark (14.7psi) for the Vtec oil pressure SW to set off the CEL code 22. This time oil pressure stayed uncomfortably low just above the #1 tick and was a bit erratic even at low rpms. In any other circumstances I would say that the oil sending unit was on its way out, but with the separate and independent Vtec pressure switches confirming low oil pressure I have to think it's OK. Looks like the next step is to very pressure at the oil filter pancake just in case. Then if I get triple verification of low pressure its on to the oil pump and on the way inspect the front head cams and rocker arms oil circuit. I'm leaning towards bad pump.

 

[Mac Attack]

It's not normal for this to happen - especially on a stock car with low miles.

If you have a bum pump verified through testing, pull the oil pan first before dropping the engine to make sure your pickup is OK. Is your pan dented in near the pickup and blocking flow? Is your pickup screen gunked up? Pickup cracked or o-ring missing?

 

[ftuhy]

Just an FYI on using heavier oil. A few years ago when Acura was racing, we had an NSX corral at Lime Rock and the head of development for Mobil 1 gave us a talk. One of the points he made about the stock NSX engine is that its machined to tight tolerances. Using oil heavier than 30W can cause premature wear because the oil is too thick to flow evenly through the bearings.

So, once your problem is solved, I'd go back to 10W-30 or 5W-30.

 

[nsxspdfreak]

Just an FYI on using heavier oil. A few years ago when Acura was racing, we had an NSX corral at Lime Rock and the head of development for Mobil 1 gave us a talk. One of the points he made about the stock NSX engine is that its machined to tight tolerances. Using oil heavier than 30W can cause premature wear because the oil is too thick to flow evenly through the bearings.

So, once your problem is solved, I'd go back to 10W-30 or 5W-30.

It was only intended for the this one test run so it's going to be drained asap. If I end up installing a pump high efficiency gears I might go to the 5/30 oil.

- - - Updated - - -

It's not normal for this to happen - especially on a stock car with low miles.

If you have a bum pump verified through testing, pull the oil pan first before dropping the engine to make sure your pickup is OK. Is your pan dented in near the pickup and blocking flow? Is your pickup screen gunked up? Pickup cracked or o-ring missing?

The pan is in good shape. I dropped it to install a SOS baffle and at the time checked the screen which was perfectly clean.

- - - Updated - - -

It's not normal for this to happen - especially on a stock car with low miles.

If you have a bum pump verified through testing, pull the oil pan first before dropping the engine to make sure your pickup is OK. Is your pan dented in near the pickup and blocking flow? Is your pickup screen gunked up? Pickup cracked or o-ring missing?

Found the post from 09 on low oil pressure that you were in on. Interesting reading. I wonder what the outcome was.

- - - Updated - - -

Next step is to verify oil pressures. I'm installing an SOS upgraded oil pressure sending unit kit and I'll be installing a mechanical oil pressure gauge at the oil filter pancake port.

 

[nsxspdfreak]

Loss of oil pressure during vtec - Update

I finally got around to installing a mechanical gauge so I could verify oil pressures rather than relying on the instrument panel gauge's accuracy. I installed the gauge in the port used for the low oil pressure light switch, which is just downstream of the oil pump discharge. I always thought the dash gauge was pretty accurate, but boy was I surprised! The mechanical gauge responds rapidly to even minor changes in RPM. In fact the needle on the gauge looked like it was directly connected to the Tach. The max pressure the dash gauge ever reads is about 85-92# (6-6.5 tick on the gauge) at high rpm (5-6k) cold and hot 42-56# (3-4th tick on the gauge). At an idle it's 14.2# (one tick on the gauge). The mechanical gauge reads about the same at an idle, but max's out at 100# plus at higher rpms (5-6K). At around 4000 it settles in at about 65#. In Vtec rpm range it remains at approximately 60-65, even when the instrumental panel gauge goes to less then 14 and the vtec low oil pressure switch activates the CEL. The higher the pressure the less accurate the dash gauge appears to be. I'm installing the SOS oil pressure sensor upgrade which comes with a new sensor and relocates it from the front cylinder head to the firewall to get it away from the vibrations. Being that it's electrical the response time is never going to be the same as a mechanical unit, but the thought of routing a plastic tube to the dash that has oil under pressure in it scares me. I had an oil pressure line break inside one of my cars years ago and it was not a pretty sight. One of my big concerns was possible loss of pressure/flow at the crank shaft, but the high pressure at the filter and right before it flows into the front end of the crank indicates that the flow to the crank should be good. Flow to the cams should also be good since that oil also comes off the front end of the crank. On the other hand oil to the vtec system and the oil pressure gauge sending unit comes from the oil leaving the far end of the crank shaft. Now that I know the oil pump is putting out good pressure the problem has to be either a blockage that's reducing flow up to the vtec spool valves, which is unlikely, or the oil is free flowing somewhere other than into the vtec rockers when the spool valves open. The next step is to connect the mech gauge to the oil pressure gauge sending unit port on the front head and then to the vtec test port. This way I can see the pressure differentials between different points in the motor, and hopefully get closer to where the problem is.

 

[RYU]

I'm not sure your pump is putting out good pressure as you suspect. I'd love to hear additional feedback from other folks, but my idle oil pressure is typically between 20-23psi (sometimes it dips to 16 when my car bogs when the AC is on at a stop light). My fwy cruising pressure (3k rpm?) is typically around 90-100 psi going off my sometimes unreliable memory. My peak oil pressure at the last track event was 126psi. Again, this is with a new oil pump OEM housing and a new Toda oil gear assembly. Btw.. I used Pennzoil Ultra Synthetic 5w30

If you have low oil pressure from a worn out oil gear I wonder if that is the cause to your abnormal cam journal wear. I wonder how many other people have the same oil pressures you're experiencing. Any idea what the manual says normal oil pressures are suppose to be?

 

[nsxspdfreak]

I'm not sure your pump is putting out good pressure as you suspect. I'd love to hear additional feedback from other folks, but my idle oil pressure is typically between 20-23psi (sometimes it dips to 16 when my car bogs when the AC is on at a stop light). My fwy cruising pressure (3k rpm?) is typically around 90-100 psi going off my sometimes unreliable memory. My peak oil pressure at the last track event was 126psi. Again, this is with a new oil pump OEM housing and a new Toda oil gear assembly. Btw.. I used Pennzoil Ultra Synthetic 5w30

If you have low oil pressure from a worn out oil gear I wonder if that is the cause to your abnormal cam journal wear. I wonder how many other people have the same oil pressures you're experiencing. Any idea what the manual says normal oil pressures are suppose to be?

Hey Ryu,
I tested it again and pressure at the midrange rpms runs between 65 & 100 +. My test gauge's scale only goes to 100 so I don't know where it peaks. The manual says 50# at the oil filter is the min at 3000 rpm and 10# at an idle, so I'm good. The Toda gears will give you some additional oil pressure but are more for increased flow at low rpms, and they allow you to take advantage of the lower viscosity oil. I'm using the 10/30 Ultra. If you missed the latest post on FB here it is.
You may have seen this already posted on FB, but just in case you didn't here's what I posted.

I took the car for several test runs after connecting the test oil pressure gauge to the Vtec test port on the front head and then on the rear head. At over 6k rpm when the spool valve opened there was 0 pressure at the front cyl head test port. Pressure on the dash gauge dropped to less than 1 and the CEL activated as it's done before. This is indicative of the oil free flowing somewhere other than into the rocker arm shaft or without the oil return restricting orifice to maintain pressure in the shaft\. On the second run with the test gauge attached to the rear head the pressure jumped from 0 to 60# when the spool valve opened. Pressure stayed at 60# until I backed off out of vtec. So now it looks like I have it narrowed down to the oil circuit in the vtec rockers and shaft on the front head. At least I now know that the pump is performing at 100% and I wasn't at risk of wiping out the motor from lack of lubrication. Tomorrow I dive into the front cylinder valve train. It almost looks like one of the vtec pins or the return orifice is missing.

Yesterday I did an air test on the vtec system and I found a massive leak somewhere between the #4 and #3 cam bearing cap. I didn't do the test 100% correctly so I have to do it again, but I'm pretty sure that's were the oil is free flowing. Most likely something I did on when I installed the new head or I'm missing a vtec hydraulic piston in a vtec rocker that I didn't catch.

Joe

 

[RYU]

That's some pretty awesome troubleshooting Joe. I'm glad it wasn't the Oil gear or housing. That is a PITA to do.

Glad you're on your way to resolving this it looks like. There's nothing like determination and some logical deductive reasoning!

 

[nsxspdfreak]

That's some pretty awesome troubleshooting Joe. I'm glad it wasn't the Oil gear or housing. That is a PITA to do.

Glad you're on your way to resolving this it looks like. There's nothing like determination and some logical deductive reasoning!

As my wife likes to constantly remind me it's my obsessive compulsive nature that keeps me going.

Part of me was hoping it was the oil pump so I would be forced to upgrade to the Toda gears, but the other part of me was dreading the possible results from driving around with no flow to the crank. It's been a great learning experience on the lubricating systems in the car. Unless the vtec system was spewing oil into the engine bay and draining the sump nothing it can do will negatively affect the oil supply (Flow/Pressure) to the cam and crank. Those Honda engineers were a pretty smart bunch.

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That's some pretty awesome troubleshooting Joe. I'm glad it wasn't the Oil gear or housing. That is a PITA to do.

Glad you're on your way to resolving this it looks like. There's nothing like determination and some logical deductive reasoning!

By the way. Penzoil Ultra is rated the best oil for keeping a lubricating film of oil on moving parts under extreme pressures. Not sure if you knew that.

 

[RYU]

Pennzoil Ultra is da bomb as the kids say

 

[integrals]

Just my experience regarding the factory specs on oil pressure.

My racecar's engine upon purchase had 'in spec' oil pressure but still have completely wiped mains. Upon replacing the mains and oil pump gear, the oil pressure measured at the oil pressure sending unit as you are, would exceed 90psi fairly low RPM (3000rpm) vs your 65 @ 4000rpm, and as regan mentioned, on load, well exceeded 100psi and maintained.

 

[RYU]

Just my experience regarding the factory specs on oil pressure.

My racecar's engine upon purchase had 'in spec' oil pressure but still have completely wiped mains. Upon replacing the mains and oil pump gear, the oil pressure measured at the oil pressure sending unit as you are, would exceed 90psi fairly low RPM (3000rpm) vs your 65 @ 4000rpm, and as regan mentioned, on load, well exceeded 100psi and maintained.

Thanks for the feedback Ravi. That's especially helpful to me since it's useful to compare notes with others. Hopefully for Joe's sake, its something else.