Rough Idle on 95 Ford Taurus GL 3.0 V6 only 60K miles... I'm lost...

[Mr. Appleton]

Well my grandfather is a stubborn fella. He barely drives and has a 1995 Ford Taurus GL 3.0 V6, with less than 60K on the clock. My 04 Jetta with 135K drives better than his car, and has had less problems, but he just won't give up on fixing it.

Two days ago he had the car on the street, moved it to the garage, car started and ran fine, pulled it in the garage and parked it there for the night. The next morning he went to get in and start it and the car sounds like its misfiring badly. I got over there and decided to change the plugs since they are original. Gapped them to .044 and still the problem persists. Grabbed a new Idle Air Control motor/valve since his was gunked up pretty bad. Still the problem remains. Checked the Throttle position sensor and it was showing an open circuit as I read the resistance while sweeping the throttle open, so I replaced that, still the car runs like dookie.

I'm lost as to what else it can be that it just randomly goes from running fine one day to running like complete crap the next. I upped the idle a little and the car seems to be running fine, almost as if the car isn't getting enough air at idle. I even disconnected the MAF and ran the car and the problem still stuck around. The MAF is clean as a whistle.

Anyone have the slightest idea what could be causing such a rough idle that the car sometimes stalls out? I got it on the road and other than idle the car seems the same, acceleration seems fine, does not feel like its misfiring at all, but at a stop no matter if you are in Drive Park Neutral or Reverse the car almost always dies.

[shaykes]

Well my grandfather is a stubborn fella. He barely drives and has a 1995 Ford Taurus GL 3.0 V6, with less than 60K on the clock. My 04 Jetta with 135K drives better than his car, and has had less problems, but he just won't give up on fixing it.

Two days ago he had the car on the street, moved it to the garage, car started and ran fine, pulled it in the garage and parked it there for the night. The next morning he went to get in and start it and the car sounds like its misfiring badly. I got over there and decided to change the plugs since they are original. Gapped them to .044 and still the problem persists. Grabbed a new Idle Air Control motor/valve since his was gunked up pretty bad. Still the problem remains. Checked the Throttle position sensor and it was showing an open circuit as I read the resistance while sweeping the throttle open, so I replaced that, still the car runs like dookie.

I'm lost as to what else it can be that it just randomly goes from running fine one day to running like complete crap the next. I upped the idle a little and the car seems to be running fine, almost as if the car isn't getting enough air at idle. I even disconnected the MAF and ran the car and the problem still stuck around. The MAF is clean as a whistle.

Anyone have the slightest idea what could be causing such a rough idle that the car sometimes stalls out? I got it on the road and other than idle the car seems the same, acceleration seems fine, does not feel like its misfiring at all, but at a stop no matter if you are in Drive Park Neutral or Reverse the car almost always dies.

distributor?

[GTE77]

Vaccum hoses? Could be a bad fuel pump if the car is'nt driven much.

[Mr. Appleton]

distributor?

I thought about that, is there anyway to check the one in the car now to make sure I don't replace another part that actually works?

Vaccum hoses? Could be a bad fuel pump if the car is'nt driven much.

I looked for vacuum leaks, couldn't find anything. I also thought about the fuel pump, but he does almost drive on a daily basis but probably no more than 5 miles a day

[JerseyVR]

perhaps a fuel filter if it is ancient

[Mr. Appleton]

perhaps a fuel filter if it is ancient

Thats the next plan of action I think.

[03GTI4Me]

I believe that generation of Taurus ate head gaskets left and right. I am assuming that all the plugs looked OK? If it is not a headgasket now, it will be sometime soon.

[Mr. Appleton]

I believe that generation of Taurus ate head gaskets left and right. I am assuming that all the plugs looked OK? If it is not a headgasket now, it will be sometime soon.

Plugs looked ok.

[r2kool4u]

Isv thing. It's a cylinder by the throttle body. Went bad on my sisters old Taurus and that fixed it.

[Turq]

I believe that generation of Taurus ate head gaskets left and right. I am assuming that all the plugs looked OK? If it is not a headgasket now, it will be sometime soon.

I think only the 3.8L cars eat gaskets. I could be wrong.

[RogerRabbit83]

I think only the 3.8L cars eat gaskets. I could be wrong.

Agreed, 3.8L's had the head gasket problem and not the 3.0L.

Vacuum leaks are hard to find, I CAREFULLY would spray brake clean or ether around the intake system and hoses to help detect a vacuum leak. If you encounter one while carefully spraying, the idle will change.

You may try cleaning the MAF as well. There are special cleaning sprays that are safe for that type of equipment.

You mentioned you replaced the spark plugs and gapped them correctly. How old are the spark plug wires? Have you replaced the cap and rotor as well?

I have had bad gas that gave the same symptoms you mentioned, that might be something to check as well.

Food for thought:

I had a 1993 Taurus L with the 3.0l (back in 2004) that I got from my Grandma. It had 24,000 miles and ran fine. When I was doing its first tune up, I wanted to check the ignition timing with my stroboscopic lamp. There is a plug you have to remove in the wiring harness (near the distributor) that must be taken out before moving the distributor. Mine was still taped up from the factory. I removed it and started to check the timing. It was way off to my surprise (from the factory) so I moved the distributor to show the correct timing marking at idle and the car ran so much better. The difference was night and day. Just something for you to look for if you dive into this further.

[MVZOOM]

If it fails under load, could be fuel filter or fuel pump. If it stutters under load and backfires, could be HT leads. Given that it changed overnight, I'd go fuel pump. Grab a fuel line, get someone to start the car and feel if there's pressure.

Cheers - Mike