Cranks but wont start after running

[patsajak]

after i run my car for a while stop and try to start it cranks and doesnt start. Let it sit long enough and it starts. What could it be?

[soryu]

ok.
the FSM
trouble diagnosis
diagnostic procedure 5 EF,EC-66

[rawgarage]

Bad starter.... Loose battery connection

[TougeSR20Kid]

Does it start up just fine when its been sitting for a while and just not start after you just drove it and tried starting it again shortly there after? I.e. 10 minutes or so?
What motor?
Which fuel pump and how old? Do you hear the pump priming?
Have you checked for spark under those conditions? Have you checked for fuel under those conditions?
Are there any other symptoms like spark plug blowout (misfiring)?
Have you checked your ecu for codes?
You need to give quite a bit more info if you want people to be able to help you out there guy...

Most often causes of a vehicle cranking and not starting after being driven are faulty crank or camshaft position sensor, faulty fuel pump, fuel pressure bleed off (leaking injector or bad check valve, fpr, etc), carbon buildup on valves and spark plug fouling.