Car won't start until is cools off?

Hi there. I have a 1995 Subaru Impreza that I have been nursing along for the past 14 years. Recently, if I drive for a decent length of time (~10 miles), tutn the car off to go into a store, and then try to start it up again, it won’t start. It turns over fine, but never fully starts. If I let it sit for 20-30 minutes, it will start back up again. The temperature gauge reads normal–between hot and cold. Is there another temperature sensor that might be malfunctioning, telling the car that the engine is too hot to start? Where/what is this called? Thanks a ton!

Its very unlikely to be any kind of temp sensor telling the car not to start.

The next time this happens, hold the gas pedal to the floor as you turn the key. If this helps get it running take it to someone, explain what is happening & how you get it running. They will (should) check your fuel pressure regulator and fuel injectors for leaking.

Thanks–I’ll try it.

A failing fuel pump can also exhibit these symptoms.
Before you crank engine on a no-start … does your fuel pump give a 2 second prime (pump noise from the fuel tank) when you turn the key to ON (before cranking)?
No prime = bad pump.

Well, it happened again yesterday. I pushed the gas pedal down to the floor and it still didn’t start. I came back to the car a few hours later, and it started right up. I’ll listen for the fuel pump prime noise. It’s just strange to me that it will start right up after sitting for a few hours.

Next try unscrewing the gas cap, and then start it.

If electrical stuff fails its first signs are often heat related failures. The gas in your tank does act to cool the pump, but it still gets hotter as it runs. It could be right at the point where its ok enough as long as it is running - but can’t get going again. Just a WAG.

So yes, listen for it to prime next time.

Well it looks as tho this post is about 10yrs old and you never got a answer. Other forums dont have a answer to this problem either talking about heat soaked starters as if it doesnt turn over when hot. The starter is fine hot or cold it just wont start the engine unless cold. Im waiting my 45min now in my 06 GMC Envoy Denali I found out its a 45-hour wait after $50 in injector cleaners and starting fluid. I can say this happened after I changed my battery

My truck has a air compressor that turns on when I turn the key so now what can I do?

If the starter is turning the engine, the non-start is not because of the starter. I’d test first for a strong spark. A CPS Crankshaft Position Sensor (or on older cars the ignition control module/signal generator/pickup coil in the distributor) can fail when it’s warm, and eventually fail altogether. With that part failing, there is not the regular strong spark needed to ignite the fuel.

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There’s also the main fuel relay to look at, which on older Hondas is notorious for failing but it’s not unheard of on other cars either.

Any time you have a crank/no start the first thing you need to do is figure out whether you’re missing spark or fuel. Once you’ve determined which of them isn’t there, you have a great start on what to diagnose. If you’re not missing either, then it’s time to start looking at timing.

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Check that fuel pressure correctly. I’ve seen this numerous times on Chevy’s/GMC’s of that vintage, and it is almost always fuel pump failing. Fuel pressure may or may not be there, but not high enough to be within spec’s.

02 Cadillac Escalade runs fine until shut off, then won’t start back up. I have to wait 30 minutes then it will start. I change oxygen sensors, fuel filter, crank sensor, and fuel relay. Please someone help.