Starting Issue

[opencasket]

Hello,

I have an issue with my 92 starting. What happens is i turn the key, wait for fuel pump to turn over completely, then crank. Once i do this the car will start for about 1 second then die immediately after. I have no CEL or any modifications other than exhaust.

Now the thing is this only happens once the car has been warmed up. If i start the car when its cold it starts up every time, no issues. If i let the car sit for about another 5-10 minutes it will usually start again, i'm guessing this is because the motor has cooled down some?


Im not sure what the issue is at this point so if you guys are familiar with this please chime in. I'm guessing / hoping that is is just a sensor or something that i need to clean or replace. And yes i have already done plenty of searching for this problem... i couldn't find anything as specific.

I have uploaded a video of the startup issue after taking the car out for about 20-25 minutes. "sorry its sideways i took it from my phone"


<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/X8fEt_uXcVo?hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/X8fEt_uXcVo?hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

Thanks!

 

[Acura NsX Pilot]

Main relay failure

 

[nikey22]

I agree, its cutting off way too quickly, so the main relay is a good place to start, take it out, take it apart, heat up all of the solder contacts, put back together, and try it again. Vibration from years of use will weaken these connections.

 

[Acura NsX Pilot]

http://www.nsxprime.com/forums/showthread.php?t=136254&highlight=main+relay

Search main relay for more threads cant be sure this is your problem but I would start here

 

[opencasket]

Main relay failure

I thought the main relay failure would cause the fuel pump to not turn over?

I can hear it turning over every time.

 

[swimmingpie]

It's probably an issue with the ignition switch. On the older cars, the switch can cause problems. When you turn the key from the "ignition" position to the "crank" position, a spring-loaded switch at the base of the ignition unit turns, bridging an electrical connection and starting the car. When the key is released from the "crank" position, it snaps back into the "ignition" position. Sometimes the switch doesn't return to the correct position or the contacts are corroded, causing a poor connection. Either the spring in the switch is broken (less likely) or the electrical contacts are corroded (more likely).

I fixed this problem in my '91 about a week ago.

1. Remove the trim piece under the steering wheel (the one with the footwell light on it) by removing two phillips screws

2. Remove the switch at the base of the ignition unit. This is not the whole assembly that you insert the key into. Just a white plastic disk-shaped piece at the bottom. It has a few wires going to it. It is held in place by two small phillips screws.

3. Chances are, the contacts are corroded. I took some 600 grit sandpaper and sanded the contacts down to bare copper. This should ensure a quality connection. If the switch is actually damaged you may have to buy a new one. They cost about $60.

also:
http://www.nsxprime.com/forums/showpost.php?p=436339&postcount=5

http://www.nsxprime.com/forums/showthread.php?p=1321838

http://www.nsxprime.com/forums/showthread.php?t=140035

 

[opencasket]

It's probably an issue with the ignition switch. On the older cars, the switch can cause problems. When you turn the key from the "ignition" position to the "crank" position, a spring-loaded switch at the base of the ignition unit turns, bridging an electrical connection and starting the car. When the key is released from the "crank" position, it snaps back into the "ignition" position. Sometimes the switch doesn't return to the correct position or the contacts are corroded, causing a poor connection. Either the spring in the switch is broken (less likely) or the electrical contacts are corroded (more likely).

I fixed this problem in my '91 about a week ago.

1. Remove the trim piece under the steering wheel (the one with the footwell light on it) by removing two phillips screws

2. Remove the switch at the base of the ignition unit. This is not the whole assembly that you insert the key into. Just a white plastic disk-shaped piece at the bottom. It has a few wires going to it. It is held in place by two small phillips screws.

3. Chances are, the contacts are corroded. I took some 600 grit sandpaper and sanded the contacts down to bare copper. This should ensure a quality connection. If the switch is actually damaged you may have to buy a new one. They cost about $60.

also:
http://www.nsxprime.com/forums/showpost.php?p=436339&postcount=5

http://www.nsxprime.com/forums/showthread.php?p=1321838

http://www.nsxprime.com/forums/showthread.php?t=140035

Thank you for the response! This is one thing that i had looked into previously, but i had only tried the "wiggling the key" in the ignition trick to see if any lights flickered or anything weird. But that all seemed fine. I will definatly take a closer look at this probably next weekend since superbowl is tomorrow :biggrin:

 

[swimmingpie]

One possible way to tell if there is a problem with the switch is to manually turn the key back to the correct position once the engine starts up. Once it cranks, don't let go and let the spring return it but manually turn the key back to the "ignition" position before the engine stalls. It should keep running. It may take some practice to get it just right but it's what I did before I fixed the switch.

 

[drew]

I thought the main relay failure would cause the fuel pump to not turn over?

It is a complex relay, powers many things including the fuel pump, ecu and other things.

So yeah, you can hear the f/p every single time *and* the MR could still be bad.

Drew

 

[pgilliam1]

I don't think any of the issues mentioned so far are heat related:

- ignition switch - if the engine turns over the switch is working (a problem
with the switch would either be not working or
intermittantly not starting). Your problem seems too
consistant.

- main relay - if the fuel pump is working everytime then the relay should
be OK (usually a bad main relay either never works or is very
intermittant and the car dies when running)

When the failure occurs, I would pull a sparkplug and check for spark and go from there.

Good Luck and Happy Motoring!

 

[soichiro1]

Sounds like an ignition switch backing to me. I am a ahonda tech and see them fail all the time.

Sometimes you will find a little dab of solder on your steering column lower cover. If it is the ignition backing the car should die as soon as you release the key. If you can hold the key between run and start it will confirm this.

Usually the main relay will cause the car not to start at all. Also on all hondas and acuras I know of the main relay will click. When you turn the key on you should here the relay click after a second or two when the CEL goes out.

If it doesnt click it's not working. Just have to remove and re-solder.

 

[Larry Bastanza]

One more thing to check is the fuel pump resistor. Disconnect it, and jump the connector harness. The fuel pump resistor is NOT used for starting, but as soon as you let the key off start, it is in use. If the resistor is open, or the connection is poor, this is the exact symptom.

Regards,
LarryB