Car won't start when hot


#1

Hello, I have a 2003 Monte Carlo 4.6 I am having a problem with starting when it is hot. I run the car down the highway for about an hour. When I stop and then try to start the car again it will only crank.

After I leave it sit for a few hours it will start no problems. Only happens when I run it for an hour or more??? No check engine light and no codes come up??? Where do I start? Noone can tell me what the answer is.


#2

Even though you don’t have a CEL, did you have it checked for stored codes?

I’m inclined to suggest a coil pack. It definitely sounds like a heat-soaking problem. When you stop the car, coolant stops flowing and air stops passing by the engine, so all the heat that’s internal to the engine (the areas around the combustion chambers are much hotter than where the temp gage is) radiates directly out of the engine and heats up the area under the hood, including everything under there that was being kept cool by the engine heat being dissipated and by the passing air.