Out of the blue one day the car acted like it was running on 5 cylinders when under acceleration or when cold at idle. When it warms a bit is still hesitates especially in overdrive when you are cruising along at 65 and go to accelerate and the 5 cylinder feel comes back. I found a cracked pcv line and replaced it along with the pcv and fittings. No change. Opinions? Mass Airflow Sensor- Idle air control valve? Dirty fuel filter? Check engine light had been on for 5 months but the car has been operating well. Last time it came on I had it scanned and it said O2 sensor running lean. Took it to the garage they checked the sensor and said it was fine and cleared the code. I would like to avoid going back to the garage at 71 dollars per hour labor to turn and screw and take hours to run down the issue when I might be able to take something apart and clean or replace myself and save a bunch of dollars. Any ideas are appreciated.
03 Taurus 3.0 Vulcan rough idle
- Thread starter RedOak
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Check the vacuum lines again, all of them, then try cleaning the IAC.
An 02 sensor that is bad could certainly throw the A/F ratio off causing it to run rough.
It's a waste ignition system, 3 coils fire two plugs at a time. Unlikely if it's an ignition problem that it is going to be just one plug. If it's an ignition system problem, you're probably losing 2 cylinders at a time.
It's a waste ignition system, 3 coils fire two plugs at a time. Unlikely if it's an ignition problem that it is going to be just one plug. If it's an ignition system problem, you're probably losing 2 cylinders at a time.
That will probably turn out to be a bad coil pack..
I'm internet-guessing ignition problem as well.
Check out "Taurus Car Club of America" (TCCA). They have a section on "understanding misfire" on their site. They've given me tons of help in keeping my old '93 Taurus on the road.
When my old 2000 did that, it was the vacuum line running off the PCV. Since you have replaced that, I would look into the O2 sensor, since you have had a code. If it is not 02 sensor, I would guess you have a coil pack that is intermittently cutting out.
Go the AAP and have them scan the code for you this will let you know were to look. also you may want to buy one of there hand held code puller so you can do it your self in the future
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I had a similar problem with the Vulcan in my Ranger. One of the plugs was fouled. Replaced plugs and it went away. Still not a very smooth runner, though, but at least it's not missing like it was.
Thanks for all the input. I pulled front 3 plugs and to my surprise they were clean. Use mmo regularly. Back three well not so easy to get to. Next will pull ias . Will keep informed.
How many miles? If over 200,000 might be a ring issue and need to check compression. May be what is called a dead cylinder with no compression. Also check the spark plugs.
130,000 miles. Motor runs well. Uses 1/2 quart every 4K
3 of the plugs looked good. Have no idea how old they are.
3 of the plugs looked good. Have no idea how old they are.
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