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Ford: 1992 Ford Explorer 4x4 4.0 liter v6, ford explorer 4x4, mass air flow sensor


Question
Hello Robert,
I have a 92 Explorer with the 4.0.  The truck has about 198,000 miles.  When I go to start the truck up after it has run, it starts extremely hard, and when the engine catches it runs rough for about 10 seconds unitll I rev it up.  I can smell some seriously rich fumes.  The check engine light does not come on so I cant check any codes.  Do you think this is my Oxygen sensor or a bad mass air flow sensor.

Thanks for your help.
Matt

Answer
A code scanner should be used to determine where the problem is located. With excessive miles, I would replace
the O2 and EGR valve, now. Also i would have the injectors
replaced or cleaned. The air idle controll valve should
be cleaned or replaced. My email is nelsonauto@g-net.net