Car has trouble starting when hot

The car starts right up when cold but if I drive around for 30 min or so, it has a hard time turning over. Any ideas? IAC valve? Coil Pack? Other fuel related issue? You can hear the car cranking fine, it just struggles to turn over. Car is a 96 Cobra with a Vortech.

Thanks

cranking fine but struggles to turn over sounds like a conflicting thing.

Does it sound like its turning over at normal speed its just not catching/starting? If so it is sputtering or anything?

Ya it's cranking at normal speed and just not catching. Car does not sputter or anything.

If you depress the accelerator pedal down to the floor and crank, does it fire up then?

I have not tried that but I thought that method has no effect on a fuel injected car? Correct me if I'm wrong. Honestly, it might be an injector leak. When I shut the car off, I do smell a little hint of gas when I get out the car. I did the blower install in November and the problem started after that.

Rev Happy said:

I have not tried that but I thought that method has no effect on a fuel injected car? Correct me if I'm wrong. Honestly, it might be an injector leak. When I shut the car off, I do smell a little hint of gas when I get out the car. I did the blower install in November and the problem started after that.

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Pressing the pedal to the floor and holding it will shut off the injectors. So, if the cylinders are loaded with fuel, this will prevent more fuel from being injected during start-up.

^ Bingo!

I asked that because you might need to make some adjustments to the tune for warm/hot start conditions. Especially due to the fact you stated this only started after your blower install.

If you believe it's a fuel injectior leak, datalog and watch O2 Sensor B1S1, B2S1 values during closed loop. If they stay pegged at ~0.9V without switching, then you know something's going on. Also STFTs can help you as well. High negative range values indicate the ECM is commanding to remove fuel, highly likely I'm the event of a leak. Spark plugs are also a great indicator too.

You can also perform a fuel system pressure test and watch for pressure drop. That would indicate a leak somewhere in the system (injectors or fuel pump check valve). I don't recall exact specs, but the system is supposed to retain pressure (KOEO: ~35-40psi) for a couple hours I believe. Someone correct me if I'm wrong.