Need help diagnosing a friends truck....

[Morphious]

Hey all, I need some help diagnosing a friends truck, below is what he sent me in detail.



Morph.



Guys, this will be a good one! I have a 95 gmc extended cab z71,

L05/MG5. Truck ran AWESOME yesterday. it started up perfectly today, idled around 1200 rpm for about 2 minutes (cold out), and then just turned off. Now, when i try to start it, it just cranks and cranks...

i get a spark from the coil, and it hurts. PLUS, there is no check

engine light when i ground the computer... it has ALWAYS given me codes... what do yall think? computer? does it HAVE to be the

computer? i know the check engine bulb isnt bad. im ****** off, fed up, and drinking keystone lights until the pain subsides.

-Adam





FYI,

while the engine was idling high, it immediately dropped rpms for a split second once or twice and went back up to the high idle. then, the truck dropped right back off to 800 rpms or so and then merely CUT

off.



LASTLY. it has the edelbrock MPFI conversion, which has worked

flawlessly for the past 4 months, except for an oil leak at the back

of the manifold, which i fixed over the weekend. timing is set at 0

degrees. check engine light came on when the timing plug was removed

as i set it, so i know the light works... . man, im confused.

 

[fest3er]

A gas engine needs three things to run:

• fuel/air mix
• compression
• spark

He has spark. We'll assume he has compression. It would appear he has no fuel.

Are the injectors working? You should be able to hear the tick-tick-tick while it is cranking (but you might need a stethoscope).

Is the fuel pump working?

Is there pressure in the fuel rail?

Is the pressure regulator working?

Is there adequate fuel in the tank?

These questions should greatly narrow down the search... .

Fest3er

 

[Paychk]

First quickest thing is go get a 5 gallon can of gas (regardless of what the tank gage says) and make sure the tank has gas in it. While you're at it put 2 bottles of dry gas in the tank (red bottle kind not the yellow) and slosh it around. Then crank it so that the fuel pump cycles several times. If it is really cold and there is water in the gas you may need to get it inside somewhere warm to un-freeze any water in the lines.



The above is based on location in a cold enough area to freeze fuel lines.