My car has Gremlins and its frustrating! Almost had enough!!

[Jetpilot3]

Hi Everyone,

Instead of everyone arguing about NSX values, NSX-R's, Tamoske, or Yaynsx, how about everyone takes a stab at trying to figure out what's happening with my car?

Here's the deal. There are 2 main issues:

#1.

I keep getting this intermittent TCS issue where in 2nd gear at 3,000rpms the engine cuts off, car shakes violently, I can hear a electronic clicking noise behind my head where the TCS box is, and the car limps into safe mode. If I glide in neutral still rolling and re-start the car and put her into gear the problem goes away. Now as per the usual NSX Prime advice everyone tells me to run the error codes following the instructions on the site (WIKI). I can't for the life of me short the Blue Service Plug located underneath the passenger footwell using a paperclip (I even switched paperclips). How the heck can I do this without taking the car back to Honda?

People keep telling me its an 02 sensor, ignition has gone bad (yet it starts), and it went away for a while when I disconnected the TCS (top connector on TCS box still leaving large connector attached in the TCS box) but it has since come back. I keep hearing intermittent electrical clicking noises coming from that TCS box behind my head while I'm driving so I'm at a loss as to what the heck is happening. Does anyone else get a electrical clicking noise from behind the drivers seat?

Last time Honda ran the error codes they said the problem was my TCS wiring harness and it needs to be replaced? But this morning I started the car and she ran up to 1200rpm and then slowly died. Started her up again and she did the same thing. Started her a third time and she ran flawlessly all day and night long. First time this has ever happened.

I'm determined to figure out what's happening to my baby and would appreciate all comments and suggestions. I think I should leave her at Honda but again they will tell me the wiring harness needs to be replaced and I'm not so sure about that as no one from Prime has suggested it.

#2. When the car sits idling at the lights the A/C doesn't blow cold and the cars air starts to get warm. When I drive off the car suddenly starts to get cold air but not as cold as I'd like it. I'm still running R12 and think its time to upgrade to R134. Could this be the A/C Circuit Board? Also, the car actually blows colder when the A/C isn't on but it still sucks! Suggestions?

Thanks for reading!

Jetpilot

 

[Ojas]

I'm not sure about the first one, but #2 could be cause by one or both of your condenser fans not spinning. Take a look at this thread.

Basically, if a fan is not working, check the fuses. If the fuses are fine, check for voltage at the motor. If there's voltage, make sure there's no debris or anything blocking the fan blades, then try to power the motor with a 12V source. If it doesn't spin, the motor might need to be replaced. If it does, the service manual says you need to remove the front bumper cover, but you don't have to if don't mind working in a tight space and follow these instructions.

 

[goldNSX]

Still have those symptoms? It's very hard to tell from x miles away but could you please explain what you did (also did not) so far to solve it? Error codes are very easy to pull. Have a look in the service manual page 769. You should be able to do this and let us know what codes if showed.

One question: Did you ever replace the main relay on the car?

@#2 R12 is more aggressive (in cooling) than R134. Your symptom has nothing to do with them, except that you're maybe low on freon. When did you check it last time? The only way to check is going to the A/C man and recharge the system. He can tell you how much was still in the system and how much you've lost since the last recharge. For example: I recharge the system every year b/c I love my compressor/money pocket (Ok, I loose a lil' bit every year but not bad for a 17 years old car and still the first system). Is the car loosing freon over time? Every older car does loose a lil' bit. You should verify that the A/C fans in the front are running as Ojas suggested. You should clearly hear them if you switch the A/C on/off. But in your case I'd check in the front inner fender if it's acually blowing air (to the wheels). I don't think it CCU related in your case but still could be as you've a 91 (old car). Has the CCU ever been revised by Briank or someone else? Not a bad idea anyway as if it's not the CCU now it sure will be in the future if there has not been a revision of it.

Hope this helps. :wink:

 

[Ko-nsx]

not sure about #1

you are low on freon for #2

 

[swerve2007]

i had my share of electrical nightmares- when you are really stuck, the process of elimination might help. borrow parts from another car and use them in yours, one at a time.

 

[drew]

#1

Have you changed out the main relay? Cleaned the battery connections?

It sounds like you are losing voltage --- somewhere---, ignition, fuel or general system failure.

I can't remember, but doesn't the fuel pump switch voltage at 3K, that relay might be unhappy. You can jump the relay to have it at high voltage all the time to see if it changes the behavior.

Issues like this is not for the dealer, they are for remove and replace parts only...not intermittent non-obvious issues (unless it is under warranty, and then they will remove and replace the entire car to fix it...but they'll never figure out the problem.) You are going to have to be personally involved: either your brain or your wallet.

2. Fans or refrigerant (freon). The fans are easy to check. If refrigerant: Get the pressures checked, or just add some

 

[goldNSX]

I can't remember, but doesn't the fuel pump switch voltage at 3K, that relay might be unhappy. You can jump the relay to have it at high voltage all the time to see if it changes the behavior.

4k. It's not the first point I'd look at. But agree, seems an voltage problem. Don't forget the grounding cables too.

2. Fans or refrigerant (freon). The fans are easy to check. If refrigerant: Get the pressures checked, or just add some

I'd not just add some. The level has to be correct. You can easily loose 200gr in the system (950->750gr) and it still works perfect. Check the absolute level of freon.

 

[Jetpilot3]

I'm not sure about the first one, but #2 could be cause by one or both of your condenser fans not spinning. Take a look at this thread.

Basically, if a fan is not working, check the fuses. If the fuses are fine, check for voltage at the motor. If there's voltage, make sure there's no debris or anything blocking the fan blades, then try to power the motor with a 12V source. If it doesn't spin, the motor might need to be replaced. If it does, the service manual says you need to remove the front bumper cover, but you don't have to if don't mind working in a tight space and follow these instructions.

Issue #1:
Nice Ojas! Thanks for the link and I'll investigate #2 this evening when I get home. For the others Brian K has already worked on my CCU.
-Refrigerant changed in October with new condenser bottle

As for Issue #2...

Process of elimination starts now:

1. Main Relay replaced and installed - issue still happens.
2. I believe I wasn't getting error codes when shorting the Service Plug because I was only sticking the paperclip into one of the 2-pin holes. I'll try it again this evening with the same paperclip going into both holes to create a loop effect. Correct?
3. Check Battery Terminals this evening for connection tightness and if they are clean
4. Suggested by Drew - I can't remember, but doesn't the fuel pump switch voltage at 3K, that relay might be unhappy. You can jump the relay to have it at high voltage all the time to see if it changes the behavior.


I'll post this evening what happens...thanks guys!

 

[Hugh]

Maybe your car is telling you that it's not happy in The UAE.

 

[Jetpilot3]

Nah she likes all of the attention...hehe.

 

[Doc308]

I know that this is the least of your concerns, but try shorting out the blue service plug with a short piece of eletrical wire, instead of the paper clip.Just strip each end and insert into terminal . At least you can get your code readings, without relying on a dealer, and can go from there.

 

[Larry Bastanza]

You really need to focus on getting the codes. You can get codes from the CEL,TCS, and ABS indicators by jumoing ther blue connector. This really sounds like a rear wheel speed sensor to me, but get the codes.

Also when the ignition is in the "ON" position, are the CEL,TCS, and ABS indicators lit during the "bulb test"? I ask because I have had an NSX in the past that seems to have no indicators, but acted somewhat like yours.

The owner had the car to a few places, and they could not figure it out. I realized as I was sitting in the drivers seat that the ABS and TCS (yellow indicators) were not lit during the bulb test. I pulled the cluster to find someone "fixed" the TCS and ABS by pulling the bulbs out!!!!!!!!!!!!!!! Once I restored the bulbs it was obbvious what was going on.

HTH,
LArry B

 

[Jetpilot3]

Larry your a champ but I don't think it will be needed. The TCS, CEL, and ABS lights are on and the flashing codes I got came from the CEL only.

Issue #1 - Weird behavior of the car:

I got the error codes - finally! Helps to connect both ends of the paperclip to the contact points on the blue plug to make a closed circuit.

I received the flashing sequence of 6 fast and 3 slow. What does this mean?

Issue #2 with the A/C not cooling the car when its idle:

Ojas and ffffanman (in Edmonton) thanks very much for showing me the problem with 10 amp fuses running the condenser motors for the A/C. I ran the car this evening in the garage where its quiet and couldn't hear them at all (10 mins or so of running). So I pulled open the fuse box under the front hood and grabbed the fuses #36 - for the left fan and #37 for the right fan. Both were shot! I'll run to the autoparts store tomorrow and have them replaced and check the motors operation again.

Please let me know your thoughts everyone.

Cheers and NSX Prime rocks! So relieved to be able to diagnose these problems...

Jetpilot

 

[goldNSX]

I received the flashing sequence of 6 fast and 3 slow. What does this mean?

Have a look in the SM for code 36 page 11-20, TCFC signal.

 

[Viper Driver]

Damn, sorry to hear that you're having all of these problems with the car!

I think you may recall when we were in the process of changing ownership that I had similar problems to what you're having, and I thought that I had solved the issue. I guess that's not the case. :frown: Does this happen unexpectedly and completely intermittently, but at around the same RPM each time? If so, then this isn't a new gremlin with the car, just one that I thought I had fixed long ago.

When I swapped out the main relay, that was but one of several steps I took to try and isolate the problem. Just so you don't go there, the ignition relay is brand new, too (Chris@SOS recommended this). After that, the problem seemed to go away and I thought that I had finally fixed it once and for all.

Here's the thread from 2005 when I was trying to isolate the problem:
http://www.nsxprime.com/forums/showthread.php?t=57073&highlight=engine+die+millisecond

I'm not sure if the "clicking" behind you is a symptom or the cause. Personally, I think that something is killing the electrics for a brief millisecond, causing the click and the loss in power. To me, the real mystery in all of this is why it happens around the same RPM each time.

The fuel pump resistor, if I remember correctly, is disconnected due to the Walbro 255 fuel pump being installed.

I am super curious as to what the problem is. I really feel for you because (when this was happening to me) it bugged the heck out of me. Let me know if there is anything I can do to help out more with this!

 

[Jetpilot3]

Have a look in the SM for code 36 page 11-20, TCFC signal.

Thanks GoldNSX! Its quite foreign to me what the manual is explaining and I don't have a voltmeter to test the TCS control unit. Hmmm...I'm looking in the manual

ViperDriver - no worries and as a side note the Type R Spoiler and other parts came in so she'll be sitting pretty by the end of the week.

This issue got the best of me this weekend and I was swearing and just had enough. Part of the stress is that I can't really trust Honda here as they are so giving me the impression that its the wiring harness and they are eager to get me to purchase it (super expensive). I'm also miffed at them for not diagnosing the condenser fans not working on the A/C system as I just had the car there. They said something about a blockage in the dash area? WTF? It might be the two fuses now that I've pulled them out...she's still my/your baby and not going anywhere but its really startling how the car shakes violently at 3,000rpms when this issue comes up! Especially when the engine dies on the freeway...

The complete interior is coming out in two weeks (wait until everyone sees what I'm having done!) so if any loose cabling needs to be looked at I'll have the opportunity. So I guess off to the store to get a voltmeter!

Any other suggestions folks?

 

[goldNSX]

Do I see somebody starting to DIY. Welcome to the club! No wonder by the experiences you got with your technician.

Believe me: Changing the fuses will cure problem #2 for nearly sure.

For #1 get a voltmeter, they're cheap. Your CEL showed code 36, TCFC signal. Maybe someone can explain this. One way to confirm code 36 would be to clear the memory of the error codes by pulling the clock fuse, starting up the car for a minute and get the error codes again. If the engine runned fine there should be no error codes. If so go for a drive until you have the symptoms described, get the codes again and see if it's returning. One question: Are you sure that there is only error code 3-6 or have you seen some others too? Again: While your car is doing this does the CEL light appear?

 

[Jetpilot3]

Chuck - this is exactly the same issue as I've now read your original post. The clicking noise behind the seat to the violent shakes when at 3,000 rpms to 4,000rpms and like you said if one day I'm cornering and this happens well there might be one written off NSX.

I noticed the issue came about in cold weather but now it does it whenever it wants to. But everything you have described is exactly what I've been experiencing.

So here's what we know:
1. Chuck replaced the ignition and 02 sensors previously
2. Chuck and I have both swapped out the Main Relay - issue still happens.
3. Error Code comes up with 36 (3 slow flashes, 6 quick flashes) and now I need to purchase a voltage regulator to test the connection or connectivity between the TCS Control Unit and the PGMFI ECU.
4. Checked Battery Terminals this evening for connection tightness and if they are clean and a okay
4. Suggested by Drew - I can't remember, but doesn't the fuel pump switch voltage at 3K, that relay might be unhappy. You can jump the relay to have it at high voltage all the time to see if it changes the behavior. Interesting that two people have suggested the Voltage Regulator.
5. OneREDNSX suggests checking the connector for the Fuel Pump Resistor
6. Spark Plugs and or their gap is suggested to be checked

 

[Jetpilot3]

Do I see somebody starting to DIY. Welcome to the club! No wonder by the experiences you got with your technician.

Believe me: Changing the fuses will cure problem #2 for nearly sure.

For #1 get a voltmeter, they're cheap. Your CEL showed code 36, TCFC signal. Maybe someone can explain this. One way to confirm code 36 would be to clear the memory of the error codes by pulling the clock fuse, starting up the car for a minute and get the error codes again. If the engine runned fine there should be no error codes. If so go for a drive until you have the symptoms described, get the codes again and see if it's returning. One question: Are you sure that there is only error code 3-6 or have you seen some others too? Again: While your car is doing this does the CEL light appear?

GoldNSX thanks for the help! For sure there will be a DIY for this issue as I'd hate for another owner to go thru this. Not neccessairly the hassle but the safety aspect of what's happening while driving. Scary.

I'll head to the autoparts place and pick up the voltmeter like you said.

yes when this happens I get the CEL light.

Question though in WIKI is says the car can store up to 3 error codes. I tested the codes this evening twice and only got the 36 code so if there were other codes how would they be shown? Eg. Flashing after this code, flashing with another type of dash light?

 

[goldNSX]

4. Suggested by Drew - I can't remember, but doesn't the fuel pump switch voltage at 3K, that relay might be unhappy. You can jump the relay to have it at high voltage all the time to see if it changes the behavior. Interesting that two people have suggested the Voltage Regulator.

It's 4k rpm where the fuel pump relay gets active. For a test drive you can take off the panel directly under the glass to the engine. On the driver side the relay is screwed to the chassis, it's black about 2x1 inch. Take a passenger with you who locates the clicking (by touching or whatever). One question: When you hear the click of the relay, does it click 'wildly' or only one time. How does your car shake? Alternating revs? This would result in more than one click if the revs always pass 4k rpm. If you shortly loose voltage it will click more than one time too.

One question: Your car has the 255lph Walbro pump which delivers more fuel than necessary. Which orifice did you choose on the AEM regulator?

 

[goldNSX]

Question though in WIKI is says the car can store up to 3 error codes. I tested the codes this evening twice and only got the 36 code so if there were other codes how would they be shown? Eg. Flashing after this code, flashing with another type of dash light?

They're stored and displayed in sequence. A code always starts with the long blinkings. In your case Long-Long-Long, and then the short ones: s-s-s-s-s-s. The next code starts again with the long ones followed by the short ones. If you've counted five times the codes and you always get 3-6 then this is the only code.

 

[Ski_Banker]

This might sound stupidly simplistic, but would it work to drive with TCS manually off for a while? If the issue still pops up, you'd know that it wasn't some bad TCS engagement issue, right? just a thought, but what do I know... :tongue:

 

[goldNSX]

This might sound stupidly simplistic, but would it work to drive with TCS manually off for a while? If the issue still pops up, you'd know that it wasn't some bad TCS engagement issue, right? just a thought, but what do I know... :tongue:

Not a bad idea. But I don't know how many times the problem occurs.

 

[Jetpilot3]

Well that might be an idea but don't know if Chuck the previous owner tried this. I certainly haven't.

Now when you say drive with the TCS manually off are you saying disconnect the TCS completely (how?) or simply pressing the button off on the dash?

The problem occurs often but its not like I can replicate it - it happens when it wants to.

I'll follow the tips GoldNSX but I've already taken off all of the partitions next to the engine window compartment and I can defintately say that the clicking noise comes from the TCS box directly behind the seat. That being said and to be sure I'll have my mate ride along and see if it acts up. It also acts up when I start the car in the am too...so I might be able to trace the issue not moving. Its 10pm and I'm logging off...

Until tomorrow...

 

[goldNSX]

Just wondering: According to this post http://www.nsxprime.com/forums/showpost.php?p=746128&postcount=16 the TCS is completely disconnected at the time of the post. Is it still disconnected?

I think Ski_Banker means by pressing the button.

Clicking from the TCS box? I don't recall a relay inside the TCS unit itself. But the fuel pressure relay is mounted on or in the very near of the TCS box. Too bad I don't have a picture of that but the SM should help you localize the parts. Good luck!

Still wondering: You've written that your car does this in 2nd. What about 3rd? Is it always the same rpm when the problem starts?

Are you able to do a video of that an post it on youtube?