Toyota car and truck forums

I have a problem with restarting this car after it has been running for a while. Once car is stopped it will not restart until the engine has cooled right down.
The car is not overheating, the battery has full charge, the starter motor works fine when engine cold.
Paper clip diagnostics read 12 and 51 only.
Where do I start to look for culprit? I would welcome any advice on this one as its very frustrating.

I assume that the engine cranks just fine, just doesnt seem to catch? How cool does the engine need to be before it is able to fire back up - several hours, minutes, engine has to be completely cold? How do the plugs look when the engine is cool - any heavy buildup, look wet, etc.? Check cap and rotor, plug wires? Did you verify when cranking, engine hot, injectors are firing fuel (use a noid light or use an automotive stethscope)?

I'd double check the resistance of your coils. Engine itself is probably fine, but the coils might have overheated, causes them to not be able to generate enough juice to fire off a plug. Also possible that the signal from the ECM is not getting to the plugs - could be any number of wiring issues (short(s), broken wire(s), loose connector(s), etc.) Could also be a dead or dying sensor (crankshaft/camshaft position sensor), bad TPS sensor, bad ECT sensor, others.

If the engine is flooding - i.e., it sounds like it wants to catch but doesnt quite get there, try propping open the throttle plate or stomp on the gas pedal when starting (opens the throttle plate and helps pull more air in, better pumping efficiency).