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1991 Mercury Grand Marquis LS 5.0L Excessive Emissions, Poor Idle Quality, Surge
Posted to Ford Driveability on 7/24/2008 25 Replies

Vehicle is idling like it has a vacuum leak(surging and running rough) but is running rich to the point where it is blowing black soot out of the tail pipe and fouling all 8 spark plugs with soot. I have replaced the EGR, MAP,IAC,and computer temp sensor. The ...

25 Replies Received (View Replies)

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Message Closed w/FIX

car Vehicle Data

1991 Mercury Grand Marquis LS

VIN 2MECM75F4M
Engine5.0 L / 8 cyl / GAS
Trans4-speed Automatic
DeliveryFI / SEFI
SymptomsExcessive Emissions, Poor Idle Quality, Surge
OccursAlways, Idle
Message Closed w/FIX

car Vehicle Data

1991 Mercury Grand Marquis LS

VIN 2MECM75F4M
Engine5.0 L / 8 cyl / GAS
Trans4-speed Automatic
DeliveryFI / SEFI
SymptomsExcessive Emissions, Poor Idle Quality, Surge
OccursAlways, Idle