Check engine light is on code says to check coolant, thermostat, temp sensor.

Asked by Dec 22, 2012 at 01:48 PM about the 2000 Mercury Grand Marquis LS

Question type: Maintenance & Repair

I have filled the coolant, replaced the thermostat and the temp sensor. The light is still on. Is there something I need to do to reset the computer or do I need to check/replace something else.

3 Answers


I don't know if this will apply here, but I had a similar issue with a Jeep I owned. After trying several mechanics in the area, I found out that only the dealer could reset the engine light. It was a way for them to get $25 from me. I never bought another Jeep because of that. They did say that, if the light comes right back on, they wouldn't charge me because it meant there was another issue that needed to be addressed. Hope this helps...

1 of 1 people found this helpful.

To reset the light, unhook your positive pole from your battery. If the light comes back on after you drive it for awhile, then you will have to take it in for service. Under no circumstances should you drive it hot. You will warp the head (s) and blow the head gasket. That cost big buck to repair.

2 of 2 people found this helpful.
Best Answer Mark helpful

I just had the same problem and I found the solution. Someone else who drove did not tighten the gas cap but rather just laid it loosely on top of the gas tank. This is an answer I have seen other people post and it appears that was the root of my problem. Now I just do not know when the light will go off.

1 of 1 people found this helpful.

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