DIY, change the air conditioning and heater blower motor on your Mercury Grand Marquis. The replacement procedure will require an 8 mm socket wrench and less than half an hour.
The blower motor on this car is located inside the engine compartment, on the passenger’s side and is basically secured by four bolts, as you can see in the image below.
Using an 8 mm socket wrench, you can remove them quite easily. We suggest you to start with the two at the top and after you deal with them, you will be able to detach the metal bracket that holds the two harnesses located there. Then unplug the harness below and move away those cables to get access to the bolts at the bottom (see detail below).
After you remove the retainers, pull out the old blower motor and work to install the replacement. Insert the new part into its place, renewing the rubber gasket that seals it, or if the old one is in good shape, keep it. Tighten the bolts and reinstall the harnesses attached to it. This is all you have to do, if you need to remove and replace the blower motor on your Mercury Grand Marquis.