[86 Trans am, 305 TPI]. I'm having this issue where cold starts are totally fine, car cranks great. But if I drive somewhere, get out, and get back in, I have to keep the pedal pressed down (sometimes to the floor) for the car to start. It will always start though if I press the pedal down about half way.

I kinda assumed this was something like leaky injectors causing the cylinders to flood after a stop. But could it be something else? Is this like a common symptom of some module going bad?

 

Wide open starts the ecm is in clear flood mode stopping injector pulse. Watch fuel pressure after a prime engine warm. If it drops off rapidly a injector or injectors are leaking.

 

check the resistance on the injectors when cold and warm.....the coils are prone to failure most often when the injectors are warm

 

Opening the throttles lets in more air. If that's what helps the car to start, then the problem is too much fuel.

So: leaky injector(s), leaky FPR. Not many other ways for fuel to flood the intake in a port EFI setup. Only other anywhere near likely way would be for the cold start injector to be injecting when it's not needed, or for the CTS to be telling the ECM that the engine is still cold. You can eliminate the CTS by simply replacing it. As parts cannon ammunition goes, it's about as low $$$ as it comes.

 

Just repeating what was said. You have injectors leaking when the car is turned off. Or possibly the FPR. I had the same exact issue with the stock injectors. I only had 2-3 leaking when the car was off. That was enough to make very hard warm starts. I had to keep the throttle to the floor if I wanted my warm starts to be quick. I don't know if they're still around but I sent my injectors to cruzin performance. They did a great job fixing the leaking ones and cleaning and flow matching the rest.

 

If the injectors are stock....don't waste your time cleaning them. Those injectors are junk. By the time you pay to have them cleaned you can replace them with a better set

 

Agree. I had no idea how old the injectors were on my V6 so I just dropped in a new upgrade set from southbay. One of the best things I have done to the car, so far.