I need some help narrowing down an issue I am having with my 1986 IROC-Z, 305 TPI.

Here are some scenarios:

1) I can start the car without any trouble when the engine cold.

2) If I run the engine for a very short while so that the operating temperature is not met, I can return to the car at any

time and it will start without issue.

3) If I run the engine until it reaches operating temperature and attempt to start the car right afterwards it will start up

no problem.

4) If I run the engine until it reaches operating temperature and then return to the car a half an hour later it takes me

about 3 cranks to get it started. Once I get it started I can turn it off and start it up again on the first crank without

issue. However if I wait another 30 minutes or so, I have to crank it a few times to start it again.

5) If I do as in scenario #4, but put the pedal the floor when I attempt to turn the engine over after it has sat 30 minutes

it will start mostly without issue.


So far I have guessed at the problem and replaced the 8 fuel injectors. However my guess was wrong. (If I remember this

correctly, the wires to the cold start injector are disconnected as it has a different chip in it) I'm not sure if it is

related but when it is hard to start I usually hear a very loud squeal come from underneath the hood until the voltage

reading comes up close to where it should be - it is really loud and sounds like maybe a belt or bearing noise is fighting

it? I can hear the fuel pump run if I turn the engine to on prior to cranking. It sounds like it is cranking at normal speed, it just doesnt start unless you crank it a few times or put the pedal to the floor while you crank it.


What most likely is causing my starting issues? I have read about all kinds of other peoples problems but I'm not sure which ones would specifically relate to mine. (I don't know how to or even have a way to check the pressure at the fuel rail or anywhere else.) But it appears that it is flooding itself out after sitting once it is warmed up. The car had a check engine light on recently but since the TPS was adjusted I haven't had a engine light since.

So what would it be most likely and why?



Coolant temperature sensor?

Fuel Pump?

Fuel Pump Relay?

Fuel Injectors? (I just replaced these)
Faulty Fuel Injector Plugs?
Bad Fuel Injector Fuses? (no idea where these even are)

Fuel Pressure Regulator?

Fuel Filter? (where is this at by the way?)

Stuck open EGR?

Distributor problems like a failing ignition module?

TPS sensor?

IAC sensor?

Gas in lines evaporating? (wouldn't make sense to me as I have to enter clear flood mode by putting the pedal to the floor to start it)

Starter heat soak? (there is a metal shield between it and the headers and it seems to crank at normal speed)

 

I have had the exact same problem as you this whole summer. Starts up fine cold, starts up fine within 10 minutes of shut down but really long cranks after a long drive and 15+ minutes of sitting.

My fix was a fuel filter.

Located on the drivers side rear of my 88 GTA.

 

Having the same problem with my GTA. First start of the day, fires right up, anything short of operating temp, as far as I recall it fires right up. Any drives and long sitting afterwards, I'm cranking forever. I am guessing you pulled the gas cap and depressurized the line at the engine before doing this job? Its possible I still have the original filter at 88K miles on the car. Likely thats my problem considering the symptoms are similar to yours.