Hey guys. I have a 91 z28 l98/700r4. My car won't start unless i prime the pump a million times for 5sec each time and on the last one i crank it for as short as possible and floor it until it starts. Sometimes it takes a few tries of this whole process and sometimes it starts right up without any priming or throttle input. When it does start it idles really bad (like a blower and huge cam, which sounds cool but thats about it) and dies when i put it in gear or give it gas. Or the idle will fluctuate up and down. And sometimes it just runs fine. What should i replace first?

 

If you simply load up the parts cannon and start replacing stuff with no diagnostics, you could wind up with more money in a still-not-running car than it's worth.

That said, the first thing to check would probably be fuel pressure at the fuel rail.

 

Thanks for the reply. I'll be back with an update soon

 

How many years has it been since the injectors and fuel pump were changed? I don't throw that out there as a recommendation to arbitrarily change them, but they're getting to be two things near the top of my preventive maintenance list. Both can have major impact on functionality, and are easier to deal with before they fail completely.

 

Ok guys so:
fuel pump and injectors could be the ones from the factory for all i know, although some of the passenger side ones have different color wires than the rest i noticed.

And as for fuel pressure:
0 with key off
45 with key on
35 when cranking
38 at idle
40 under load
Pressure begins to drop immediately after shutting the car off and reaches zero in like a minute

 

If the pressure drops, either you have leaky injector(s), regulator, or fuel pump.

If it's the regulator, it will be leaking into the vac fitting. Unplug the line right after you turn the car off and see if fuel comes out.

If it's injectors, you can disconnect the main plug, take em all out as an assembly, let it prime, and see if any drip.

If it's not either of those, it's the pump.

 

Ok so. What's the main injector plug look like? And you mean take all the injectors out? Like pull the plenum and the runners and the rail and all that?