1997 Mercury Grand Marquis - In the morning, the car starts fine but after a few minutes of driving, the car will usually stall especially if I'm at a stop. The car usually starts right up again and it will be fine as long as I keep driving it.If I let the car sit for an hour or two after driving, the car is very difficult to start. It cranks but doesn't fire up. After it eventually starts, a cloud of grey smoke comes from the tailpipe that smells strongly of fuel.Once it's started, it drives and idles fine.
Country: United StatesMake: MercuryModel: Grand MarquisYear: 1997
Checked for trouble codes, checked and cleaned wiring connection on crank position sensor
Thanks for your question. Sorry you're having car problems, I will do my best to apply my research and supply you with an accurate answer ASAP. You will need to see if it has spark when it won't start and also check the fuel pressure with a gage. The possibilities are; Fuel pressure too high or too low from a possible bad pump or regulator. Bad CRANK sensor or bad coolant temp sensor. Let me know if you need anything else. Hope this helps you. Thanks, Ron
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Thank you for your advice. When the car wouldn't start easily this afternoon, I attached my scan tool to the OBD port and noticed that the coolant temperature was intermittently showing -40F instead of the actual temperature of about 90F. When the car warmed up, it showed the correct coolant temperature. I'm going to replace the coolant temp sensor.
There's your problem, they go out of range like that and cause these issues. That was one of the items I mentioned to you. See attached waveform of one with a problem like yours. Thanks again, Ron
It was your comment that had me looking at the temp sensor. I drove it around all day today with no problems. I'm calling the problem solved because of your advice.Thanks!
37 years experience
Good deal. Thanks, Ron
I received a follow up request email. I'm satisfied with the answer and you should have received your credit. Is there something more I need to do?
No, everything turned out fine. Thanks, Ron