Dead NSX....

Periokid · 7 May 2003

OK, I drive my car and it runs fine, but it has been a little hard to start for a while. Nothing alarming.

The car sits for a week and when i go to start it, the engine turns over fine but won't start. Not even a hint of trying to catch.

Myself and a friend swapped out a few parts: Ignitor, Ecu. Main relay.

I can hear the fuel pump run for 2 seconds prior to turning the key to start.

The car has a comptech supercharger. The are no fault codes from the ECU. I am thinking it might be the comptech FPR. Maybe it is letting the fuel run back to the tank with little fuel pressure in the system?

Can anyone help me diagnose this problem?

Ojas · 7 May 2003

You mention "Not even a hint of trying to catch." Do you mean the starter not engaging the flywheel?

If so, can you hear the starter solenoid? This should be click as the starter gear moves out (to engage the flywheel) when starter starts, then click again when you stop cranking as the gear moves back in.

Also, when you say "it has been a little hard to start for a while", I'm curious, do you mean A) engine cranks at the normal speed, but it takes more turns for the engine to fire up or B) engine cranks kinda of slower than normal, but fires up after a while. If it's B, maybe the starter could be the problem.

Periokid · 7 May 2003

Perhaps my description was lacking...

When I say the engine turns over, I mean the engine spins fine via the starter motor. The starter is operating perfectly.

The hard starts I was talking about were a delay in firing, not a slow spin from the starter.

I wish it were as simple as the starter.

The DON · 7 May 2003

I had this problem a couple years ago and was told that the fuel pump main relay behind the driver seat was faulty, try swapping that with your friend.

Periokid · 7 May 2003

Thanks for the tip...

but as stated in my original post, that was one item we swapped out.

I hoped it was that! But alias, it was not.

kpond · 7 May 2003

Check for spark and fuel pressure while cranking... and narrow down the possibilities by 50%.

daveh · 8 May 2003

Hey there,just like Kpond said check for fuel and spark.best place to start.Doe's the check engine light go off after 2 sec's,like when you hear the fuel pump stop?.Spark is kinda tricky to check for ,but if you watch the tach while you're cranking ,if the ignitor is firing then the tach will dance a little.not a lot ,almost to 400rpm .If you see the tach jump then you know the iggy' is sending it's signal to the coils. Highly unlickley you lost ALL youre coils .You could have washed down the Cylinder walls too.Especially if it's been sitting ,if you flood it out ,It'l get so much fuel on the walls that it'll lose enough compression to give you a no start,Blah,Blah,Blah.Any way just like Kpond said ,Basics first . Fuel & spark?.Ck Eng light.Keep mailing .Can't be that hard to fix

Taj · 9 May 2003

Sometime it could be as simple as a weak battery since you stated that it get harded to start with respect to time. You also mention that your car has been sitting for a week and a worn battery does not retain its charges.

Periokid · 12 May 2003

daveh said:
Hey there,just like Kpond said check for fuel and spark.best place to start.Doe's the check engine light go off after 2 sec's,like when you hear the fuel pump stop?.Spark is kinda tricky to check for ,but if you watch the tach while you're cranking ,if the ignitor is firing then the tach will dance a little.not a lot ,almost to 400rpm .If you see the tach jump then you know the iggy' is sending it's signal to the coils. Highly unlickley you lost ALL youre coils .You could have washed down the Cylinder walls too.Especially if it's been sitting ,if you flood it out ,It'l get so much fuel on the walls that it'll lose enough compression to give you a no start,Blah,Blah,Blah.Any way just like Kpond said ,Basics first . Fuel & spark?.Ck Eng light.Keep mailing .Can't be that hard to fix

Yes the check engine light goes off when the fuel pump stops at 2 seconds. The car only sat for a week after running fine. The only thing is that is has been a little hard to start.

Periokid · 12 May 2003

Taj said:
Sometime it could be as simple as a weak battery since you stated that it get harded to start with respect to time. You also mention that your car has been sitting for a week and a worn battery does not retain its charges.

All the cranking certainly wore the battery down. I put it on a charger and it still won't start. It seems to crank at full power.

Larry Bastanza · 12 May 2003

Hi David,

Are we at the point of deciding if it is spark or fuel? If so , I thought of something that may easily tell us. Get a can a starting fluid, blast some into the throttle body and crank it up. If it fires even once, you know you have a fuel problem. Then we can go from there.

Did you get the fuel pressure gauge from Russ??

Let me know. If you want we can try to make a plan to get together.

HTH,
LarryB

Taj · 13 May 2003

You are right, your battery must be low at this point. Try jump start your car. Charging a worn battery (not under-charged) is not going work.

If the battery is weak or worn, you simply can't go by the way it cranks. Bring your battery to Pep Boy or Sears to have it diagnosed. One simple way to diagnose the battery yourself is leave most of the electrical accessories on, turn on the head light, radio, A/C fan....etc and crank, or use a battery from another car. How about fuses such as fuel pump?

I am not familiar with the ignition system detail, but low voltage can also contribute to weak spark if the voltage drop below a certain threshold.

Like Larry said, the next step is spark and fuel.

daveh · 14 May 2003

hey there,once again ,it needs fuel ,spark and compression.WHAT DO YOU HAVE??????????????.By the way most starting fluids contain ether I've seen someone in our shop put a rod through the block of a lexus from detonation using starter fluid.Not recomended IMHO.

Larry Bastanza · 14 May 2003

Hi DavidH,

WOW, I have used it many times. I do not go crazy with it, just a squirt or two. Did this guy dump a lot in? Sounds like he made a small bomb

Thanks,
LarryB

daveh · 14 May 2003

hey larryB.exactly major detanationand possibly hyrolock too I always use carbklean if i'm trying that method of Diag.I don't hink it has any ether in it and is not as combustible.He did have it WOT so I'm sure that didn't help.

Larry Bastanza · 14 May 2003

Thanks David,

I will keep it in mind for the future.

LarryB

Taj · 14 May 2003

Is it dead or alive ?

Taj

nsx_parts · 24 May 2003

THe suspense is killing me!

Periokid · 24 May 2003

it is dead...

the car seems to get fuel. the exhaust smells of gas when I keep trying to start it.

i found a weak ground at the output of the ignitor and corrected it. it still does not start. i then tried another ignitor, no luck.

i checked the main relay again and it seems to be working properly.

i am clueless.

BadCarma · 24 May 2003

Periokid, if you have validated that you are getting fuel or simulate it via above mentioned priming of intake using whatever brand x start fluid or carb cleaner ..fuel is ruled out. you state that on the first attempt after sitting the car turned over but would not start, from your message it sounded as if it was turning over strong until you perhaps wore down the battery. you checked the ecu, igniter,relay. I assume by now you checked spark (pretty easy. on to my point), it sounds like you have been methodical in your trouble shooting. if you did not have the s/c it would be easier.
question..are you running larger injectors(how much larger then oe if you are) with stock ecu which could support the wash down issue but thats not where im going.this is out in left field and I am reaching so guys cut me some slack on this scenerio,it is unlikely but at this point worth a shot. from past forum threads and I am very unsure about this I believe I read some models,years had a two piece flywheel and the outer ring could become detached and just spin with the starter motor not tranferring the power to the motor. is this even remotely possible given the range of fixes he has tried. if this was the cause would it not make a racket,lots of noise.it could account for the fact the motor is getting fuel,spark and not kicking.its the only other thing I could think of other then washdown.I am not even sure it was the oe fly that had this issue and believe I read it was corrected. like I said I am reaching so go easy.I just want to see this fixed as it is driving my trouble shooting sense nuts!

best regards david
ps for the record if someone whom experienced the flywheel issue was it very apparent? good luck and keep us posted!

daveh · 24 May 2003

Have you still not checked for spark?Your'e missing one of the key ingredients.I'd guess that if youve got spark that you're washed out.I think he'd hear something if the ring gear was off the flywheel .plus he wouldn't get any injector pulse if the cam ain't spinning .No crank sensor input.SPARK MAN SPARK.DO YOU HAVE IT OR NOT

DocL · 24 May 2003

Have you pulled the plugs yet?

From all this starting and fuel being injected to the cylinders, I wouldn't be surprised if the plugs were fouled. That may expalin why it turns over but doesn't run.

Good Luck.

Periokid · 27 May 2003

Update...

Still dead

Fuel seems ok.

Spark seems absent.

Two potential problems found and corrected...

1. poor ground to ignitor. Fixed.
2. tranmission ground bolt stripped resulting in a very loose transmission ground. Fixed.

I am worried that the poor transmission ground may have caused the engine to seek another ground. If that ground is burnt out as a result, it could be the reason why I still cannot get the engine to run.

Could a damaged ignition switch cause the motor to crank but not start?

nsx_parts · 27 May 2003

You need three things to make an engine run.

1. Fuel/Air Mixture

2. Spark

3. Compression

If you test with starting fuid, and the motor runs, you have confirmed that #2 and #3 are good, leaving a fuel/air problem.

#3 is an easy test, get a compression gauge and spin the motor. Test all 6 holes. A broken timing belt will show up with this test on non-collision engines.

#2 is an easy task ass well. Put your finger in the coil pack.

You need a clear answer to point to one of the above to drill down to the real problem.

Good luck PK

T Bolen · 30 May 2003

Not quite on topic here, but when you get the problem solved change your oil right away. You do not have a fuel problem, and you have been cranking many times which allows unburnt fuel to linger in the cylinders. Some of that fuel can weep past the rings and get in the oil, reducing the lubricity of it.
Hope you get it fixed soon!

Dead NSX....

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