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Ford Taurus Wagon 1999 Engine Misfire

My taurus wagon’s transmission has been slipping or maybe “hesitating” in the last 6 mos, particulary when engine is cold and accelerating from a stop. Recently, it has gotten worse, some days more than others. I took it into a transmission specialist and they told me that the engine was misfiring which was causing the troubled shifting. Their solution is a full engine tune up to take care of the misfiring. Will this solve the problem or could there be other reasons? They did mention that i have coolant loss and they would try to chase down the leak.



Did the mechanic mention retrieving any misfire codes?

If it is missfiring the check engine light should have came on and there should be a code in the computer such as:

PO300 "Random cylinder missfire"
OR
PO301 cylinder 1 missfire
OR
PO304 cylinder 4 missfire

Etc.

nope, he did not mention codes and the “check engine” light was not on.

Another thing is that it seems that when i need to slow down and brake, i am always having to fight against the engine (in other words, it feels like about 20% of the braking power is used to fight against the idling engine). when i let off the gas the car coasts forever b/c the engine is still delivering some power. the car idles normally at about 1000 rpm but the car won’t slow down when you let off the gas. i’ve driven other cars and when you let off the gas, the transmission slows you down. not mine. my friend has a taurus and has the same problem as i do. is this a throttle control issue or is my transmission just not as refined/smart as some newer transmissions?

I would’nt worry about any so called engine missfiring until after the high idle problem is corrected.

If you look under the hood you will find vehicle emmisions sticker.

I’d bet it states that warm idle should be around 6 or 700 RPM’s. NOT 1,000. This is why you are “fighting against the engine.”

Some possibile causes for the high idle are a:

Defective ECT/engine coolant temp sensor

Binding throttle linkage.

Dirty throttle body.
The ECT raises the idle on a cold engine & might be incorrectly telling the PCM/computer that the engine is always cold.

See this link for info on how the ECT works.

http://www.kemparts.com/TechTalk/tt13.asp

i went to advance auto and the code was cylinder 2 missfire

Attaching & using a vacuum gauge is VERY SIMPLE to do.

See this link for more info:

http://www.users.bigpond.com/ergoff/vac1.htm

Putting the vacuum gauge on it is the first test that I would do on this.

Some of the possibilities for code PO302:

Faulty spark plug or plug wire.

Low compression

Bad fuel injector

Bad coil