When the engine is warm it hesitates to start

1993 CADILLAC ELDORADO
83,000 MILES
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MARK WEBER
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I have the car listed above Touring, 32 V-Northstar Engine. When the engine is cold this vehicle starts up without any hesitation. After I drive it and park it for about an hour or two, the engine cools down to about 180 – 130 the vehicle hesitates to start. Any idea what would cause this problem?
Nov 7, 2011 at 8:05 PM
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SQM
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Hello,

Just to clarify the no start issue only happens when the engine is hot?

If the starting issue only exists when the engine is hot, it could be due to vapor lock in the fuel system.
Excess heat can boil fuel in the line and vaporize it. The vaporized fuel creates back pressure in the fuel system. This will prevent fuel from going into the engine.
It can also happen due to clogged vent lines. It will make the vapor mix with fuel to rush out and create starting issues when hot.

A good first step would be to test the fuel pressure when the engine is hot.

This vehicle should have 40 - 50 PSI of fuel pressure, with the key on and engine off.

Here is a helpful guide:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Please let me know if you have any questions.
Thank you.
Feb 3, 2022 at 9:11 PM