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Mercury Cougar Engine Questions



  • PF_FlyerPF_Flyer Pennsylvania Furnace, PAPosts: 7,745
    With a little digging (I always try to learn something every day) I'm thinking it may be a problem with your engine coolant sensor since so many aspects of the engine management systems like fuel, ignition, and emissions are affected by engine temperature.

    This makes sense to me and is where I'd check first (or have my mechanic check). If the sensor is malfunctioning and "thinks" that the engine is already at operating temperature, then the computers that now run our cars think that everything is ready to go as if the engine is warmed up, but since it's not, the computer trying to run the engine is using the wrong "settings".

    Sound reasonable?

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  • decrottydecrotty Posts: 15
    No codes, no check engine light. You're the one who changed the gas filter, plugs wires. Three things I had trouble with:
    1. take off the air intake. Just inside there may be carbon clogging a couple of little holes.
    2. There's differential pressure sensor that goes bad. Two types. One metal located just under the air intake, or it could be plastic just around to the back of the engine.
    3. Take off the ignition coil block. Look at all the connectors. All should be shinny. If one is carbon dull, that one is missfiring. Replace the ignition coil.
  • redcat99_redcat99_ Posts: 4
    That's something to definitely look into pf_flyer. Thank you!
  • redcat99_redcat99_ Posts: 4
    Thanks decrotty, I will definitely look into this too!
  • vtraudtvtraudt Posts: 52
    Car dies while driving.
    Jump start keeps it running until battery is drained.
    Back of alternator has pos battery voltage, and continuity (so 'mega fuse' is good).

    Is there another fuse in the charging circuit that could be blown?

    Other checks that can be done before alternator has to come out for testing?
  • aussieechoaussieecho Posts: 22
    while the engine is running stroke the wires coming out of the air box to see if that settles things down. If so clean them. Those wires are part of the air temp sensor, this helped stop a squeeling we had when cold
  • jmays2jmays2 Posts: 2
    I have a 2000 Cougar with the 2.5 V6 that needs replaced. It has an automatic transmission.
    Can I replace the engine with a 1999 2.5 that has a standard transmission?? ( i don't want to swap the standard trans because it is broken)
    I am new to cougars so any info would be greatly appreciated.
  • jvoelkejvoelke Posts: 2
    I have a 2000 Mercury cougar V6 2.5, Upon starting the car and backing out I give the car gas and it putters a little then gets up to speed, when it hits about 20 it bucks a couple times, If hold on to the gas it gets worse if I take my foot off and replace it it seems to get better, but it takes forever to get up to speed. When it finally hits about 40 it does the same thing, about every 20MPH.. when steady on interstate it is fine, unless I give it gas to go about 5 more MPH it bucks again. The code at autozone read misfire on 4 and 6.. Ive read all over and people are saying it's either just a tune up, or the neutral saftey switch.. I can't make up my mind on which it is and I don't want to do both right now, So im asking if anyone knew which one it is for sure? Thanks
  • usmustrustusmustrust Posts: 2
    edited August 2011
    Hey man I have the same car. I can probably help you with any problems you are having.

    I just swapped the engine myself a few weeks ago and got some misfire problems also.

    If you do the following you'll definitely eliminate the problem you are having right now.

    Fuel Injectors (remove your fuel rail and inspect the injectors for leaks)
    remove each injector from the rail, clean it and the rail itself, scramble the order of the injectors and re install them each into the rail)
    Fuel Injector connectors remove the connectors formt the injectors, clean them with no residue electronics cleaner and reinstall...use dielectric grease on the contact when u reinstall.

    Spark Plugs
    Get NGK TRG55K sparkplugs - they are the platinum ones
    install them and put dielectric grease on the wire connector, sparkplug ceramic and the connector that the wire goes on

    Upper Intake Manifold Gasket take it off, clean it with rubbing alcohol, get hi temp silicone from your local parts shop and put it on the gasket then reseat the gasket to the Upper intake Manifold...

    Throttle Body Cleaner

    follow the instructions on the bottle. When I had my Upper Intake off the car, i just sprayed carb cleaner inside of it ,,,,scrubbed it best i could and sprayed the heck out of the throttle body opening with the cleaner

    After doing these if you still get a misfire change your coil pack you can get a new one from or goto a local auto wrecking yard and pull one from another cougar.

    reinstall everything back together....these few tasks should take anyone with basic mechanical know how about 3 hours or less to complete and I pretty much guarantee your problem will disappear. Good luck feel free to write me with any questions etc.
  • change the fuel rail pressure sensor. also take it into the shop and they have a code sensor that tells you what is wrong with it. i have the same car did the same thing changed it and it does not do that anymore all i have to do now is get another sensor because of something else and i am all done. dont listen to the guy below that is way to much work. any further questions just ask.
    you can get the part at any ford dealer.
  • I have had my Cougar for about 4 yrs. Just before we bought it the previous owner replaced the alternator. about 1 1/2 yrs later the alternator went out and I took it to a starter/alternator place and had it rebuilt which lasted about a yr. Took it to a different starter/alternator place and the car ran great except the battery light would flicker at about 5500 RPM+ but the mechanic couldn't find any problems. It lasted about 1 1/2 yrs and went out again. Took it back to last starter/alternator mechanic (who only charged me labor) to fix it. Still not fixed since the light starts to flicker at various RMP' s now. Any suggestions??? I have about had it with this ongoing problem... thanks
  • Did u fix your problem? I have exact same situation and dont know is it the PCM or the factory alarm or what else could be. Let me know please. Thank you
  • I have a 200o Mercury Cougar special edition and I am having so many problems. The first problem is that the gas gauge sometimes work but the majority of the time it doesn't can anybody tell me what's going on with that. Then the second problem is that the car jerks a lot when your going over 5o. Lastly today of all days the car just shut off without any notice and will not start at all. Tried cranking it several times but nothing happened. All the lights come on so there is nothing wrong with the battery can somebody answer any of these questions I would be grateful. Thanks in advance.
  • sounds like fuel starvation, disconnect the fuel line off back of engine where it connects to the fuel rail. Put glass jar under coming line and crank engine. Fuel should gush out of line from fuel tank. If not, fuel pump filter or pump might be problem
  • The fuel pump on that year was replaced on warranty. That's exactly what happened to me when the car was about 2 yrs old.
    As for the fuel gauge, the fuel tank has to be removed to get at it. While doing that check the wiring to the tank.
    That being said, similar things happened to me much more recently and it turned out to be the ignition coil.
    An error code has probably been set. Go to Auto Zone and ask them to read the code. They might be able to point you in the right direction.
  • i removed the fuel pump/gauge from the top. Under the rear bench is the access door. Lid likely very difficult to remove (I had to use hammer/chisels to turn the lid).

    not a bad idea to have a spare lid and o ring/seal on hand (from same guy/junkyard you get the new pump assembly?).

    I could not fit the hole assembly through the hole in the sheetmetal, so I did a few surgical cuts with the sheetmetal snippers and later bent those down again (and sealed with epoxy).
  • is it hard to put in a new motor in my 1999 do i do it. thanks! :confuse:
  • hi im also having the same problem with my sisters 99' mercury. i wanted to know if u ever found the solution to that lose hose? if u could pls reply back that would be appreciated.
  • missrutmissrut Posts: 2
    Did you ever figure out your problem? I am having a similar problem. My car when started the other day ran rough. I turned it off and it would not start again. changed the fuel pump and it ran great for 4 days until I filled it up with gas. now it is doing the same thing and we tested the old fuel pump last night and it works fine. so it was not the fuel pump to begin with. And we have no idea what it could be.
  • ratscats23ratscats23 Posts: 3
    edited May 2012
    I just had major work done on my car cylinder head replaced,waterpump,starter,thermostate,egr feedback sensor get all of it back together and this little plastic elbow shaped breather i think comes tumbling out from under car.We have no idea where this part came from.Im gonna try to upload some pictures can ">someone please help<img src="C:\Users\jenny\Documents\Desktop\attachments\IMG_20120518_021106.jpg
  • ratscats23ratscats23 Posts: 3
    edited May 2012
    please can someone tell where this part goes just post the above url in your browser and the picture will pop up
  • ratscats23ratscats23 Posts: 3
  • vtraudt1vtraudt1 Posts: 3
    Your photo link does not work (at least for me).
    Try again. Not sure how it works here, but there is a "IMG" button in the bottom. Or upload photos to photobucket or similar free web hosting side then post the link to it here.

    I have a ton of Cougar stuff that goes to the junkyard very soon.

    you can also email me to

  • Hey folks any help would be great. I have an 02 cougar C2 edition v6 I am replacing the fuel pump for the 4th time in a year. Any ideas what could be causing it.
  • If you haven't already done it, I would:
    1. Switch to a different gas station.
    2. Switch to a different parts store.
    3. Switch mechanic tech.
    4. Pour a bottle of Seafoam into your gas tank with EVERY OTHER gas fillup.

    Outside of those items, perhaps there is some type of electrical issue? The Fuel pump is such an item that it is somewhat rare to need replacement so often.

    Hope this helps.
  • That fuel pump was a subject to recall back then. You may be buying the defective pumps from resellers. Go to a Mercury dealer for the new pump. If that car hasn't had the recall you might get it free. Otherwise you will be sure to get the better pump. It might be a bit more expensive but it will work.
  • my son owns a 1999 cougar and I get a p1518 how do I fix this it is a intake manifold runner stuck open
  • davvvesdavvves Posts: 1
    My 1995 Cougar wont pass the smog test. The check engine light is on, but it passed every part of the test except the air injection. So the emissions passed but the functional check failed. Anyone have experience fixing this?
  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaPosts: 57,564
    You might find THIS VIDEO helpful

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