Mechanics

WON'T STAY RUNNING

1985 Ford Crown Victoria • V8 2WD Automatic • 180,000 miles

Car cranks fine when cold. After running just a few seconds, it will shut off. Have replaced mapp sensor & throttle control sensor. If I unplug mapp sensor, it will crank but I must hook it back up real quick. New plugs had a lot of soot, cleaned them, but to no avail. HELP
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Jerry vonier
February 14, 2011.




I have some questions. Have you checked fuel pump pressure? Has the check engine light come on? Have you checked the idle air control and MAF sensor? Have you checked to make sure the catalytic converter is plugged? If you keep your foot on the gas, will the engine continue running? After it dies, will it restart and do the same thing or does it refuse to start? If it doesn't restart, have you checked to make sure you are still getting spark and fuel to the engine? Any major vacuum leaks?

Sorry for all the questions. I'm just trying to get a feel for what has been done and what exactly is happening.

Joe


Check eng. Light not on. Cats don't exist, was told that was problem so they are gone. Will keep running w/ foot on gas. Won't restart unless unless maff sensor is unpluged. Plenty of spark & fuel. All vacuum leaks repaired


Tiny
Jerry vonier
Feb 15, 2011.
Just to satisfy an old man's curosity, unplug the cannister purge solenoid to see if it helps. It is located under the battery area.
We have run into a few of those when we had the early to mid 80's Crown Vics.
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Tiny
Way2old
Feb 16, 2011.
Try what way2old mentioned to see if that changes anything. The fact that it won't restart after it shuts tells me either the fuel pressure is low or weak spark. Let me know what you find when you unplug the purge solenoid. Also, when it doesn't restart, make sure the fuel pressure is within spec and you have a good hot blue spark.


Could my problem be water in the gas. This started all at once.


Tiny
Jerry vonier
Feb 16, 2011.
It could be somethhing that simple. Have you tried using drygas?


The sensor was shorting internally and grounding the 5 volt reference to the PCM.


Tiny
Way2old
Feb 16, 2011.
Da***t, the gas is clean, my luck it couldn't be that simple. Have ordered a new EGR valve ( gasket was history on old one). Installed a new coil. What does cannister purge valve look like? Is it small round w/ 3 vacuum lines?


Tiny
Jerry vonier
Feb 17, 2011.
Here is a picture of it.


Tiny
Way2old
Feb 17, 2011.

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