need help - Hello. My friend has 97 Chevy truck with a V6. Everything was fine until one morning it just wouldn't start. It cranks but doesn't even try to ...

Hello.

My friend has 97 Chevy truck with a V6.

Everything was fine until one morning it just wouldn't start.

It cranks but doesn't even try to start.

I first checked the spark, and all 6 cylinders have it.

Fuel pump is buzzing and after a cranking for a while you can smell gas from the exhaust pipe.

Have not yet checked fuel pressure. Should I?

I was able to check sensors with my laptop through OBD2 connector.
CPS, MAF, MAP, temperature sensor all give consistent output while engine is cranking.
Also, I was able to get a code for multiple cylinder misfire.

To my it feels like something is wring with ignition timing.

Any Ideas?

Thanks.

Yes I'd check fuel pressure, sounds like your fuel pump is going... it takes more pressure to start it than it does to actually run.

When you turn the key the fuel pump runs for 2 seconds, it does not shut off when the correct pressure is reached... so try this: Turn your ignition key on and back off real quick (just enough to turn over the engine), then turn the key so the fuel pump kicks on and turn it back off. THEN try and start the truck. Cycling the pump on a few times can build up enough pressure to get it started.

Timing is controlled by the computer plus or minus 2 degrees. So unless your distributor is loose its most likely good.

Ok.
I'll try that.
If it doesn't work, then I will check it with pressure gauge.
By the way, what is the correct fuel pressure?

Thanks.

I just took the fuel pressure and it is 58psi with key on and 65psi while cranking.

nikch86 wrote:I just took the fuel pressure and it is 58psi with key on and 65psi while cranking.

I'd say those are good readings, if I recall the min was 62psi to start.

Will double check if the ignition did not jump and then compression.

Is the distributor loose? can you jiggle it by hand ? thats a common situation with vortec motors with a lot of miles on them, cant tell you how many ive repaired just by tighting the hold down...and you say youve checked the crank and cam sensors?

How to check them?
I thought that crank sensor is fine because when one on my other car died I wouldn't even have spark because ECU did not know if the engine was turning, so it wouldn't give spark or gas.

Have you tried a interchangeable ecm yet?

I do not have any spare once.