1995 Z28

Bought 4/7/96 to replace 88 iroc bought new


Installed New plugs
Oil/ filter
Sprayed cylinders with fogging oil
They turn over
New fuel filter
Drained gas
Put 1.5 gallons back in and drained again


It turns over, but won't start:
Fuel pressure injector gauge bumps to 42lbs when ignition turned on then falls back to 38lb
Spraying starter fluid in the throttle body will cause it to run until it burns out. I'm thinking it's some type of fuel problem.

any suggestions on where to go next greatly appreciated

 

Hi there! Have you replaced the optispark? Looks like you did everything else but a fresh optispark, plugs and wires may be the next thing. Also change out your fuel filter.

 

I've replaced the plugs and fuel filter, I have not replaced the opti spark. If I run a scan 94/95 will it tell me if it's the opti spark ?

 

Unfortunately no. If the opti has been in the car for a while, it wouldnt be a bad idea.

 

The opti would be the original that came in the car.
Thanks

 

If it runs on ether. Gas that old can't be any good?

 

The gas was drained . Actually put some more back in it and drained again before trying to start,

 

Well if it fires on starting fluid you know there's spark,I would expect a gas issue especially after sitting that long.
Probably gummed up injectors etc.
There may be some bad rubber gas lines imploding,I'd replace every rubber line in the fuel system as old as the car is and sitting for years likely with ethanol gas in it.
I put non-ethanol clear premium and Stabil in my car when she gets parked for winter,even just sitting over the winter months with today's gas can cause problems for a fuel system without Stabil and that goes double with ethanol gas.

 

You have fuel pressure and no fuel. Next is to check for injector signal. This can be done with a noid light. There are many ways to check for this signal but I always recommend noid light to guys without a electronic background. The noid light is designed to check for signal and it has the correct resistance to verify there is enough power to fire the injector but also not draw too much power which can fry the PCM. Some voltmeters and test lights will draw too much power. A well equip tech will check the signal with something that will see the square wave. That a little overkill for a no start.

If you have fuel pressure and signal to the injector telling it to fire injector is all that is let. I would pull a easy plug and verify it is dry. On the surface gummed up injectors are the most likely scenario, but I hate guessing.

Most chain parts stores will loan you the noid light (with a credit card to secure it) and they can be bought at harbor fright on the cheap. You can also by single noid lights at most parts store but you will pay half what a set will cost.

 

Thanks for the information! I decided to go ahead and replace the optispark and in the process of doing now. Replacing the water pump and plug wires while I've got the front of the motor accessible. If it doesn't start the fuel injectors will be the next project. I had no clue what to check. .Thanks again!