QuestionQUESTION: Hello Ray:
Volvo starts normal sometimes but other times it takes 7 - 8 seconds. If I shut it off and start it soon after, it always starts right up. I have a new fuel pump, fuel filter, plugs, air filter, air pump, & control valve. I do have an CEL light(evap)on. Volvo dealer did a fuel pressure check and recommended new pump but never said anyting about fuel pressure regulator. Please tell me what to check, every answer from Volvo cost me an hour labor charge and the problem has not been corrected.
ANSWER: Greg,
Put a fuel pressure gauge on the car and then drive to warm it up. Park it and monitor the pressure it should not drop below 25 psi in the first 45 minutes. If it drops there is an internal leakage between the pump and the rail. Pumps fail and so do the regulators. Injectors leak lines leak also.
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QUESTION: Ray,
I'm going to check fuel pressure as you suggest but I always wait until the new fuel pump shuts off, so shouldn't it have enough pressure?
ANSWER: Greg,
With the gauge installed start the car warm it up, get it hot, note the pressure. Turn off the car and monitor the fall in pressure, it should remain above 25 psi for about 45 minutes.
As for the last question I do not understand what you ask.
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QUESTION: Ray, I installed a new fuel pump. My start sequence goes like this: 1st. I turn the key to the "on" position and wait for the fuel pump to run and then shut off. 2nd. I turn the key to the "start" position. Because I wait for the pump to re-pressure the fuel line, why should it matter if the fuel pressure drops after the car is parked? Thanks for your help! I do appreciate the advice.
AnswerGreg,
If the fuel has leaked back, air replaces the area fuel was, so priming it as you are doing may not be enough to fill the line and rail. There is the matter of the air that needs to be purged, so hence the longer crank time. You maybe right in thinking that you are filling the line. I was only trying to advise how you can test the fuel system for that leakage.
