NSX won’t start. It cranks .not the battery.

Toothy

Toothy

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3 December 2021
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Location
Long Island
Hey all,
So I’ve been having intermittent issues with my 99 Targa. I did search the forms and I know there may be issues with the main relay or the starter itself …maybe the ignition switch under the dash.

The history of the problem is the car started immediately every time I tried to start it. Then one time it just cranked for about a minute .. Wouldn’t start.
I left it alone …started it again a few hours later right away no problem.
It’s done that intermittently since then. It will work fine for a couple of days then I can’t start it.. I would try a few times and it would turn over.

This time I can’t get it to start at all no matter how long I wait …I tried to jump it with my blazer..it’s not the battery. It just cranks and cranks and cranks and cranks. I hear clicks when I turn the key to accessory / on.

Do you guys think this is a problem with the starter, solenoid,the relay, or the ignition switch? Please keep in mind I’m not on y’alls level when it comes to mechanics!
 
Stkpikr said:
Have you ever changed out your gas filter? My NA1 would act like that until I changed it out. The paper filter had disintegrated blocking fuel flow.
Click to expand...
No.. but I just talked to my local Honda/Acura specialist and he thinks it’s the main relay and that I probably flooded the engine by constantly trying to get it to turn over. I ordered a main relay from the local Acura dealership.. (one day delivery) and I’ll see how it goes. My spark plugs are probably soaked
 
Sounds like your main relay as your dealer suggested.
A whack on your aft bulkhead with a closed hand is an old trick to get the cracked solder joints to function and if the car starts, it is almost 100%.
Most dealers have to back order the relay, they can be repaired, and I believe are also available from like Rockauto.
 
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Miner said:
Sounds like your main relay as your dealer suggested.
A whack on your aft bulkhead with a closed hand is an old trick to get the cracked solder joints to function and if the car starts, it is almost 100%.
Most dealers have to back order the relay, they can be repaired, and I believe are also available from like Rockauto.
Click to expand...
Lol is the “aft bulkhead “ the panel behind the seats? Because I removed that panel(such cheap attachments) and beat the relay like a red headed step child….to no avail.I told u I’m a mechanical dullard
 
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Miner said:
Sounds like your main relay as your dealer suggested.
A whack on your aft bulkhead with a closed hand is an old trick to get the cracked solder joints to function and if the car starts, it is almost 100%.
Most dealers have to back order the relay, they can be repaired, and I believe are also available from like Rockauto.
Click to expand...
Yea man, I called my local Acura dealer and they are getting a relay for me tomorrow. a bit over $100 but I can't complain seeing as I just called them today and they will have it tomorrow. Best I could do on eBay was 4-5 days and questionably OEM. I'm pretty sure my engine is totally flooded though. Any way to "clear" the gas out of the engine? My Honda guy told me to slam the gas down all the way after I swap the Relay when I try to start it. 🤔
 
If the engine is cranking over, it is definitely not your starter motor!

Based upon your description, the main relay or the ignition switch are likely candidates although there is lots of other stuff that can cause a non start condition. The common 'tell' for a main EFI relay is that when you switch the ignition switch to the run position and most of the dash lights come on; but, the check engine light does not illuminate (the check engine light should illuminates for a couple of seconds on first power up) OR you don't hear the fuel pump go through its 2-3 second prime cycle on first power up.

The main EFI relay is a 'two for one' package with two relays in it. One relay powers up the ECU and the other relay powers the fuel pump; but, the fuel pump relay is controlled by the ECU so if the ECU relay is dead the pump will not prime and the CEL will not illuminate. You can also have a dead pump relay in which case the CEL will light up; but, the pump will not prime.

If the relay is dead, save it. Failure is typically due to solder fractures on the circuit board and you repair it by reflowing the solder so that you can keep it around as a spare. Do a search and you will find a number of threads describing reordering the relay.

If the problem was a dead main EFI relay you did not flood the engine because the fuel pump will not run with a dead main EFI relay.

Watch your dash cluster display. When you turn the ignition switch to run, with the exception of the CEL do all the warning lights come on as per normal and can you turn the radio on along with the heater fan? If the warning lights don't come on or you cannot operate your electrical accessories then the problem may be your ignition switch, not your main EFI relay.

If it turns out not to be the main EFI relay this time, putting a new relay in anyway on a 1999 car will never be a bad thing. The main relay on my 2000 died last summer. It died and stayed dead - none this maybe yes maybe no stuff. It conveniently did this right in front of my house and since I have been carrying a Rock Auto spare around in my trunk for the last 5 years we were under way in about 30 minutes. Unfortunately I did snap a couple of the retaining clips for the interior panels and those clips which are NSX only are not stocked in North America so I had to order them from Amayama in Japan.
 
Old Guy said:
If the engine is cranking over, it is definitely not your starter motor!

Based upon your description, the main relay or the ignition switch are likely candidates although there is lots of other stuff that can cause a non start condition. The common 'tell' for a main EFI relay is that when you switch the ignition switch to the run position and most of the dash lights come on; but, the check engine light does not illuminate (the check engine light should illuminates for a couple of seconds on first power up) OR you don't hear the fuel pump go through its 2-3 second prime cycle on first power up.

The main EFI relay is a 'two for one' package with two relays in it. One relay powers up the ECU and the other relay powers the fuel pump; but, the fuel pump relay is controlled by the ECU so if the ECU relay is dead the pump will not prime and the CEL will not illuminate. You can also have a dead pump relay in which case the CEL will light up; but, the pump will not prime.

If the relay is dead, save it. Failure is typically due to solder fractures on the circuit board and you repair it by reflowing the solder so that you can keep it around as a spare. Do a search and you will find a number of threads describing reordering the relay.

If the problem was a dead main EFI relay you did not flood the engine because the fuel pump will not run with a dead main EFI relay.

Watch your dash cluster display. When you turn the ignition switch to run, with the exception of the CEL do all the warning lights come on as per normal and can you turn the radio on along with the heater fan? If the warning lights don't come on or you cannot operate your electrical accessories then the problem may be your ignition switch, not your main EFI relay.

If it turns out not to be the main EFI relay this time, putting a new relay in anyway on a 1999 car will never be a bad thing. The main relay on my 2000 died last summer. It died and stayed dead - none this maybe yes maybe no stuff. It conveniently did this right in front of my house and since I have been carrying a Rock Auto spare around in my trunk for the last 5 years we were under way in about 30 minutes. Unfortunately I did snap a couple of the retaining clips for the interior panels and those clips which are NSX only are not stocked in North America so I had to order them from Amayama in Japan.
Click to expand...
Wow thanks for that very detailed response. As far as I recall.. all of the other electrical stuff worked. I will run through your checklist in the morning before work. Very much appreciated! That goes for the rest of you as well…

Also.. do I need to disconnect the battery prior to swapping out the relays?
 
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UPdate: car started this morning first try in low 60 degree weather..after not starting 20 times yesterday in 80 degrees. i hope its the solder joints in the main relay. Gonna fix it this afternoon.. will update. thanks again all.

and again.. is it a good idea to disconnect the battery prior to the swap?
 
It sounds like a Main Relay or Ignition SW for sure..
I still use my original Main Relay on my 1991. I re-soldered it once as preventative maintenance 6 years ago. I also have a new spare in the glove box at all times. I also replaced my ignition switch as a preventative measure.
99% of the time re-soldering a Main Relay will bring them back to life. A good solder flow will make them better than new.
 
The main relay is a plug (relay) and socket (body wire harness) arrangement. No bolts / screws, just unplug so as Miner notes you should have no need to disconnect the battery. After 23 years, the socket may be really stuck on the relay so you may need to carefully pry it off with a flat blade screwdriver working around the edge of the relay to gradually work it off. Just make sure that the ignition switch is off.

In your previous failed start attempts, was the CEL coming on when you switched the key to run? If it was, then the pump side of the relay may be failing intermittently; but, your 23 year old fuel may may also be approaching the end of its life. If the CEL was not illuminating, then it is most likely the main EFI relay. Since you have a replacement relay on hand, start with the relay since it is the high probability failure point.

You might want to take Warrenw's guidance and also order an ignition switch since that is a device that is subject to wear and really annoying intermittent failures. Switches that start to operate erratically can be pulled apart and sometimes cleaning and applying Deoxit or conducting grease will restore them. I replaced the ignition switch on my 2000 preemptively. I also have a new Denso fuel pump sitting in a box should my fuel pump ever fail. If you think you might want a spare pump and want to go with an OEM pump you may want to start looking early since Denso was having 'supply chain' issues.

These cars are now approaching post middle age and the aftermarket supply of parts is drying up. Acura (at least in Canada) does not stock a lot of the parts resulting in critical back orders which really seems to be lip service. If you want a part that is going to be on critical back order its better off to just order it from Amayama in Japan. If you don't want to be out of service for extended periods of time you may need to plan ahead for stuff that eventually will wear out.
 
Old Guy said:
The main relay is a plug (relay) and socket (body wire harness) arrangement. No bolts / screws, just unplug so as Miner notes you should have no need to disconnect the battery. After 23 years, the socket may be really stuck on the relay so you may need to carefully pry it off with a flat blade screwdriver working around the edge of the relay to gradually work it off. Just make sure that the ignition switch is off.

In your previous failed start attempts, was the CEL coming on when you switched the key to run? If it was, then the pump side of the relay may be failing intermittently; but, your 23 year old fuel may may also be approaching the end of its life. If the CEL was not illuminating, then it is most likely the main EFI relay. Since you have a replacement relay on hand, start with the relay since it is the high probability failure point.

You might want to take Warrenw's guidance and also order an ignition switch since that is a device that is subject to wear and really annoying intermittent failures. Switches that start to operate erratically can be pulled apart and sometimes cleaning and applying Deoxit or conducting grease will restore them. I replaced the ignition switch on my 2000 preemptively. I also have a new Denso fuel pump sitting in a box should my fuel pump ever fail. If you think you might want a spare pump and want to go with an OEM pump you may want to start looking early since Denso was having 'supply chain' issues.

These cars are now approaching post middle age and the aftermarket supply of parts is drying up. Acura (at least in Canada) does not stock a lot of the parts resulting in critical back orders which really seems to be lip service. If you want a part that is going to be on critical back order its better off to just order it from Amayama in Japan. If you don't want to be out of service for extended periods of time you may need to plan ahead for stuff that eventually will wear out.
Click to expand...
Sound advise.
No the CEL light did not come on ( as far as I remember) everything in the dash was working normally. Radio and fan worked.

Is this the ignition switch of which you speak ( I know its not OEM)
https://www.autozone.com/batteries-...h/p/duralast-ignition-switch-ls852/190325_0_0

Can't find it on the Amayama site..

Thanks for all the in depth info OG
 
It looks like the correct part. The way to confirm would be if they provided a reference to the OEM part number which is 35130-SL0-003. For a genuine OEM switch at Amayama the cost is even lower

www.amayama.com

Honda 35130-SL0-003 (35130SL0003) SWITCH COMP., STEERING

Honda 35130-SL0-003 (35130SL0003) SWITCH COMP., STEERING. New & genuine Japanese car parts. Fast shipping. Low prices. Request a quote from Amayama Trading Co. online.
www.amayama.com www.amayama.com

However, the shipping kind of eliminates the savings if the Autozone part can be sourced without shipping costs. However, wait until you do your main relay replacement. You will likely snap some of the plastic retaining clips for the interior panels (I did) and they are typically unavailable in North America. If you need clips, order them from Amayama at the same time you order the switch and the incremental shipping cost for the clips will likely be $0.

Just for comparison, check out Amayama's price for the main relay

www.amayama.com

Honda 39400-SL0-003 (39400SL0003) RELAY ASSY., MAIN

Honda 39400-SL0-003 (39400SL0003) RELAY ASSY., MAIN. New & genuine Japanese car parts. Fast shipping. Low prices. Request a quote from Amayama Trading Co. online.
www.amayama.com www.amayama.com

​

 
Old Guy said:
It looks like the correct part. The way to confirm would be if they provided a reference to the OEM part number which is 35130-SL0-003. For a genuine OEM switch at Amayama the cost is even lower

www.amayama.com

Honda 35130-SL0-003 (35130SL0003) SWITCH COMP., STEERING

Honda 35130-SL0-003 (35130SL0003) SWITCH COMP., STEERING. New & genuine Japanese car parts. Fast shipping. Low prices. Request a quote from Amayama Trading Co. online.
www.amayama.com www.amayama.com

However, the shipping kind of eliminates the savings if the Autozone part can be sourced without shipping costs. However, wait until you do your main relay replacement. You will likely snap some of the plastic retaining clips for the interior panels (I did) and they are typically unavailable in North America. If you need clips, order them from Amayama at the same time you order the switch and the incremental shipping cost for the clips will likely be $0.

Just for comparison, check out Amayama's price for the main relay

www.amayama.com

Honda 39400-SL0-003 (39400SL0003) RELAY ASSY., MAIN

Honda 39400-SL0-003 (39400SL0003) RELAY ASSY., MAIN. New & genuine Japanese car parts. Fast shipping. Low prices. Request a quote from Amayama Trading Co. online.
www.amayama.com www.amayama.com

​

Click to expand...
Damn that's a big price difference (For the relay.)
I got mine for $140 overnight at the Acura dealership. Ordered it yesterday and they had it for me within like 16 hours.
I got scared for a minute because the Part number of mine is different than the one you posted ...but I think yours is for 1991-94 models. mine is 39400-SL0-A01


I'll put it in tomorrow AM. And hopefully that's that. I already had the rear panel of and the clips seem to be in order. Its kind of a cheap feeling set up ( the rear panel) maybe that's just me.

Thanks again for the advise. I'll def keep everything in mind as far as hording parts for the future.
Hopefully gasoline will still be legal hahah..
 
Ok so apparently the relay is not behind the firewall compartment on a 99. It seems I have to remove the side passenger panel as well? Damn

Is there any resource or direction on how to take the storage pocket behind the passenger seat and “b-pillar trim” out? I don’t Want to force anything or break any fasteners.

Edit.. I just popped that "storage pocket out the same as the firewall trim.. just held with fasteners.. gonna unscrew the side panel and see how it goes. it look like only 3 screws.

I got the 3 screws out but don’t know exactly how to get the trim all the way out.
I see that there is some metal hook near the window but I can't for the life of me figure out a path of removal.
It also appears I'm going to have to remove some other electronics in order to clearly get to the Main relay. It looks like I’m going to have to take those gray and blue harnesses out as well?
Apparently what I thought was a 5 minute fix is gonna be a bit more than that.
 

Attachments

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OK I got that interior side panel out.. there are three clips that are actually imbedded in the soft waterproof trim. I had to bend the trim back a good bit and get a screwdriver behind the clips and move them from behind the frame to the outside. Its gonna be a bitch to put that back in.. was i supposed to remove the soft trim prior.. hope not.
 
OK !!!! I got everything done and It started up just fine.. hopefully it will repeatedly do that.

If any intermittent fails in the future I will bump this thread and we can focus on the next step.

i'm going to find that thread about re-soldering the old main relay and keep it.
I've learned a lot and i appreciate all the help.

I'm def gonna order some spare parts from that japanese site .

Ya'll give me a rundown of what you think are the most important things to have (things that may be real scarce) other than Ignition SW and fuel pump.

be well everyone , Anthony.
 
Sorry for the panic on the relay number - I just went to Amayama's site and wasn't careful with the year. The relay for the later cars is same part number; but, ending in A01 instead of 003. The last three characters are revision numbers and reflect the fact that the relay changed locations during the production run from its previously sort of easily accessible location to the more hidden location requiring the removal of the right side panel. The actual relay guts are identical. The mounting bracket and the way it fits on the case changed. You can pop the guts out of the relay case and switch cases if you need to mount a new relay in an older car or vice versa.

When looking for parts watch those last three digits / revision numbers. If you shop EBay or Amazon or non Acura vendors, sometimes you can get hits with the same part name and number ; but, with a different revision. Sometimes revisions are minor (they changed the color of the plastic in a clip) and the part is forward / backward compatible. Sometimes the revisions reflect serious functional changes - don't try and mix the power steering control units between different years.

Did you manage the change without breaking any of the white plastic retaining clips? If so, you did better than me.
 
A few of The White retaining pegs were separated from their metal attachments on the vinyl panel. But the white pegs themselves were intact I just had to slide them back into their housing.


The biggest issue was just getting that B pillar interior passenger side panel out. Once I remove the three screws for the side panel there were those metal clips…Those metal clips are inbedded into the weatherproof lining. I got it done. Nothing broken !

Sorry if I’m not getting the proper names of the parts correctly.
 
Throwing this out there for the future, main relay solder problems affect damn near every 90s Honda, but if this wasnt a permanent fix, another common crank but no start problem without a CEL tends to be the crank sensor. I've seen this happen on many different makes of cars and they are a pain to diagnose as some flowcharts dont always jump to this conclusion till a lot more diagnosing is done first. Wires, magnets, heat, you get where I'm goin with this.
 
Hi, guys,

I just replaced the main relay on my '99, and just for future reference for others planning on doing the same, the main relay is held on by both a 10 mm bolt AND a zip-tie (which I had to cut to remove, but didn't replace for the new main relay), just fyi, so have the appropriate tools on hand to deal with that, too.

Oh, and another thing, if planning on replacing the fuel resistor relay in the engine bay, the old bracket seems impossible to remove from the old resistor relay (the two bracket screws won't budge!) - plan on buying a new bracket and screws - trust me, ha!
 

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