My car’s engine does start, but when I turn it off and then try to restart the car, the engine runs too rich. I have to leave it for about an hour before it will start again. The fuel regulator has been replaced, but the problem still persists. What is your advice for what will solve my car’s problem?
If you have confirmed correct fuel pressure when you changed the fuel pressure regulator, I would next check the engine coolant temperature sensor for the fuel injection system. That sensor, if failing, is generating a false "cold" reading, causing the injection system to run too rich. Also check the thermo timer portion of the cold start injector circuit. That system may also be generating a false "cold" reading, causing too rich of a mixture. If you would like to have this checked, a certified professional from YourMechanic can come to your car’s location to inspect the starting problem.
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