Clean the inside of the throtle body where the butterfly is. Also clean the idle speed control which is on the side of the throtle body. Good luck. 11/11/04 - just happened to me. My mechanic is going to; 1) replace EGR valve He also found a leak (with a special leak detecting gadget) at the intake manifold, so that gasket is being replaced. Check your pcv valve, this on thing can cause a lot of troubleshooting. Only 3-5 dollars to buy.
There are several things that can cause your 2000 Mercury Mountaineer from running. The most common cause is a lack of fuel. You might want to start by changing your fuel filter.
The power steering might whine on a 1998 Mercury Mountaineer because the pump or reservoir is low on fluid. Check the reservoir and add fluid to eliminate the whine. You may have a leak in the system.
the misfire my be caused by improper sparkplug gaps or bad injectors
Look at your temperature gage...If that is low, you might have a bad thermostat, which would keep your heater from working...I would check that first. also, check the cab air filter. i had the same problem. temp was fine but the filter was full.
The door ajar light might stay on in a Mercury Mountaineer if a door is not shut properly. Sometimes a door will seem like it is shut, but will not be shut enough to trip the light off. Check for dirt or other debris in the door latch for all doors.
When a sunroof will not close on a 1997 Mercury Mountaineer, check to make sure that the hinges are not rusted. The fuse for the sunroof mechanism is in the fuse box in the dash on the driver's side. It might be possible to close this manually, if the hinges move freely.
sticker in the glove comparment or you can program your own with the manual or go to the dealer,they might charge for it.
I have a 2002 Moutianeer, and not to long ago had a problem with the shifting. It would struggle, then shift real hard into 2nd. I had to have a tramsmission overhaul done. Thank God it was under warrenty.
the battery
you might have installed it upside down or the new thermostat might be defective or the wrong temperature range it could also be something unrelated, possibly a blown fuse
the fuel pressure regulator on the fuel rail might be bad
Similar problem. Tyrned out it was a hose that was slightly dry rotted and the cracks were keeping the system from establishing a good vacuum. Check for any hoses that might be cracked.