I have a 96 Z28, it's got 150k on the odometer and it starts great when its cold. As soon as it get warmed up it doesn't want to start. I can finally get it started but I have to puch the gas to the floor and hold it there while cranking the motor over to get it to start. It takes an average of 10 to 15 seconds to start. I think it might need new plugs/wires, and the injectors cleaned. If anyone else has any input, let me know. thanks

 

If the plugs wires etc were the problem, it would have a cold problem as well. It could be something ignition related breaking down when it gets hot BUT, you mentioned restart. If the ignition components were dieing from heat, it should crap out before you shut it down.

To me it sounds like you are flooding with fuel after it's shut off. By flooring the throttle, you put the PCM in flood mode and it reduces the pulses to the injectors while it's cranking. That occurs usually from 2 things. Either the FPR has a hole in it and leaks fuel into the intake but is not likely. Or, more likely, you have a sticky injector. Both problems can be observed by viewing the fuel pressure after the engine is shut down. If either is a problem, the pressure will drop fast.

The first thing to do is check your oil for fuel smell. If so, you know the consequences. The second thing to do is check the vac line for the FPR and see if it is wet. If so, replace the FPR. The next thing to check if they are ok, is the injectors for leaking. Unbolt the fuel rails and lift them with the injectors out of the intake so all the tips are visible.

Then apply 12 volts to the fuel pump prime connector and pressurize the fuel system. With the pressure up and the injectors out, you can visibly see if any are leaking. If it turns out you have a bad injector, you can have them cleaned and flow matched or simply buy a matched set of aftermarket injectors.

Dave