Question about 1996 Mercury Grand Marquis

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Windows and O2 Sensors

3 of the 4 windows don't work and constantly fall, is this something a do it yourselfer can fix or does it need to go to a shop? I was told it was the regulators, but I have no idea. Also, I was told the O2 sensors needed replaced. How many of them are there, where are they located, will I need any special tools, and can I do it myself? I'm not very automobile smart when it comes to these things, so any help is appreciated.

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Yes. you can do all this yourself. the windows are fairly self explanatory once you pull off the door panel. they are probably off track, or have a broken or loose actuator cable (the regulator shouldnt cause them to fall). the O2 sensors are also simple. they are located in the exhaust (v6 or v8 has two before the cat converter and one after 4cyl has one before and one after) a special tool is needed for O2 sensors but is is not expensive.

Posted on Feb 11, 2014

Testimonial: "Can you give me anymore info on how to fix the windows? I had this same problem with a 2000 Buick I had and I just ended up disconnecting the window motor and using a ziptie to hold the window up. Also, it is a v8 model and after I posted the question I was told that one of the O2 sensors was already replaced, but they don't remember which one. Is there a way to test them to figure it out?"


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SOURCE: more 99 cougar problems

there is a fuse for the o2 heaters if one of the sensors blew the fuse they will all be out

Posted on Mar 01, 2009

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SOURCE: o2 sensors on a 99 mercury cougar v6

I just got done replacing the O2 sensors in my 99 Cougar due to throwing a P0135 malfunction code. There's 3. Facing the engine there's one in the front coming off of the front header, which is easy to get to. Another more tricky one if between the engine and the fire wall on the rear header pipe. The third is under the vehicle behind the transmission pan on top of the exhaust. In order to replace the O2 sensor near the fire wall you will need to remove the 4 retaining bolts for the ECM module and move it out of the way. Additionally you will need to remove the 2 retaining nuts for a wiring harness that is seated below the ECM module. Pay close attention to the connectors because the front and under vehicle O2 sensors have round connectors the one near the firewall has a squared connector. I was able to replace all 3 by myself in approximately 35 minutes. If your throwing a O2 heater malfunction code it is most likely going to be the sensor near the firewall. make sure that you know someone with a code reader so the code can be cleared. If you're do for an emmissions inspection be sure to put at least 40 miles on the new O2 sensor with different types of driving (e.g. highway, coasting, decellerated turns and rapid acceleration). Gotta love project cars for your kids!!

Posted on Apr 04, 2009

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