2009 Toyota Corolla difficulty starting after sitting over 30 minutes engine warm

Question

Starter motor runs for 3 seconds or more after 2009 toyota corolla has been sitting 30 minutes or more and engine is still warm.

If engine is cold it starts fine. If engine is warm but only sitting less than 5 minutes it also starts fine.

The longer it's been sitting the longer it takes to start, if when starting the engine is still warm.

Pushing down the accelerator when starting doesn't seem to help much.

There is definitely a linear relation between how long it takes to start vs how long its been sitting, if the engine is warm. If its been sitting for 1:30, the engine is still a little warm and it may take 6 seconds for engine to finally start.

What could be causing this ?

Answer 1

The fuel injectors may be leaking, due to wear, sticky build-up, or o-ring failure. The warmth of the engine vaporizes the leaking gasoline in the intake manifold, causing an abnormally rich condition upon starting. The longer the car sits, the more excessively rich, requiring more cranking time to clear the intake manifold.

You could check for this possibility by removing the plastic cover on the air filter after the warm engine has sat for some time. Remove the air filter and put your nose into the induction housing, close to the throttle body shutter. If you smell a strong gasoline oder, the injectors are leaking.