i have a 89 iroc 350. the problem is that the car will turn over but not start sparaticly.sometime you go to start and it starts right up other times it will just crank without firing.But if you spray carb cleaner in the intake it will start right up and continue fine.I put a new chip in it and it still does it, I put a new ignition control module in and it still does it.I assuming its on the fuel side due to its starting with carb cleaner. Does anyone think this is an ECU problem maybe??

ANY HELP IS GREATLY APPRECIATED !!!!!!

 

Sounds to me more like the Fuel Pressure Regulator or Fuel Pump. Try this with the engine off take the cap off of the valve on your passenger side fuel rail. take a screwdriver or something with a point push the little valve down, if fuel does not come shooting out it is your fuel pressure regulator or fuel pump. If you turn the key to the run position and listen you will be able to here the fuel pump running if you hear it then it is the fuel pressure regulator. Also change the fuel filter if you have'nt already.

 

Keep a fire extinguisher handy using that method.
Use a fuel pressure tester. It MUCH safer and buttloads more accurate.

 

i just whent through something very close to that with my gta. after replacing well lets just say a lot more then i should have come find out i had bad injectors two of them. i had two injector that where stuck open and if you let the pump prime it would flood the engine. good luck

 

Well I do work on a poor mans budget, but yah keep one handy

 

i know the fuel pump is running so i will try the regulator next i guess. if not that i guess i will try a new ecu.

 

hi ,do u still have the tuned port setup on yours ?if so sounds like the coil connector wires ,mine was doing the same thing !the wires connect from the ignition coil to the distributor. have someone spin it over while you wiggle the wires,thats how i found mine !

 

its not that i just replaced the coil with the msd one.It does not seem to me ignition (i think) but i did just order a adjustable fuel regulator from tpis today.Im hoping the advice of Jay29 works !!!

 

sounds hugely simple to me........ You said the pump runs that means you have power to it.

the ignition is obviously not your problem if it runs on carb cleaner.... The computer i also doubt hugely has any part in this. Check fuel pressure at the rail, guranteed low pretty much by the sounds of it, if so you've narrowed it down to an obstruction between the pump and the rail or the pump itself, knowing how gm pumps have always sucked its probably that but, if it were me i'd blow out the fuel line and put a new fuel filter on just to be sure (but, i prefer not to throw parts at problems before i know for sure).

btw i'd take ur ignition parts back if you are still able as it sounds like that has nothing to do with it.

as for the problem being injectors that i highly doubt because, u seldomely ever c quite a few injectors all at once go bad, which it would have to not to run.