20 Most Recent 2000 Mercury Grand Marquis - Page 6 Questions & Answers

"Long term fuel trim"; it's running a little too lean. Check your fuel pump pressure & flow.

it should be on the right side on the handle in the trunk it should be a four number pass code

Check the brake switch on the master cylinder. When it leaks it can cause multiple issues in cluding your concern

If you are talking about the housing that the radiator hose connects to, it should be held on with two bolts. If you mean the part that the thermostat sets in, that is part of the intake manifold.

Run self test on heater control head if electric temp control. .key on, press off and floor buttons at the same time for 2seconds then release and press auto button for a second, ck what codes show on heater control head. Then Google the code. .probably the blend door actuator

There should be an access door on headliner.if not, you'll have to remove, lower headliner...I would start at the fuse panel and make sure the fuse is ok

Did you check the crank sensor and all the fuses? Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/sean_54c3a3dc48a7773c

Who diagnosed the vehicles problems? Who replaced the parts & why? How were the replaced parts tested & what were the results? Where is the car now?

My old man had the same problem. His car jerked around 30 to 40 mph and it turned out to be one of the injectors.

It could be as simple as a bad vacumn line. Those doors are controlled by vacumn from the engine. The engine heat sometimes deteriorate the rubber and they crack or fall off. See if you can find a bad or broken vacumn line .....it will be going toward the firewall.

That is one of the hardest problems as it could be an intermittent problem. In other words your chasing a short that my not show the first time you check using a multimeter, but could show up later and then disappear. I would check to see if there is a code readout for the problem or just take it to Advanced Auto Parts or AutoZone and they will allow you to use their mechanic's OBD Code Reader which should provide the code that will tell you the location to look. For all I know it could just be a bad fuse under the steering wheel.

I was told there wasn't one on this model

If you turn on key and none of gages or lights react check battery and if thats ok check the ecu fuse and or a fuseable link.

I'm showing a fan clutch on the water pump instead of an electric fan on the radiator.But you could have both.The computer takes the signal from the temp sensor on the intake manifold to determine engine temp. An electric fan should come on around 230 degrees. There is a relay between the fuse and the fan motor.