@150K, there is a Strong chance that you have low oil pressure. As such, there is a electronic oil pressure sending unit on the lower front right side of the block. Unplug it for a few seconds. If your check engine light goes away, theres your problem. I personally would hook up a $17 manual oil pressure guage just to be safe. As for the cruise controll problem, this is a common problem. just outside of the transmission, there is an electrical attachment to a vehicle speed sensor. Check both the wires leading into it and the connctions at the sensor itself. Replace at your descretion. As for the o2 sensor, it is possible, but not likely. o2 sensors will rarely set of a trouble code on an EFI motor unless you have a cylinder not firing.
The most common cause for a cruise control that stops working is that the electrical components or switches have stopped working. Sometimes taking it apart and cleaning the contacts will fix the problem.?æ
Change the cruise control switch.
Yes, it can cause the cruise to surge.
where is the heater control valve
where is the ignition control module located on mercury marquis
check fuses then refer to the speed control sensor which is on the throttle body closest to the air intake hose that controls the engine idle and speed control. Good luck.
Take it to the mechanic.
The wiper control module on a 1998 Mercury Grand Marquis can be found behind the instrument panel. It is close to the steering column, on the right side.
i have a 2002 grand marquis and when i driving on the highway at speed of 60 to 70 the light of traction control star to flash way is the problem
Check your fuses and wiring to the control first.
behind you glove box
check your air idle control valve