Help On Family Driver T-bird

[racer24]

My 1989 t-bird has picked up a intermitent tmiss at idle. So far the mechanics have tuned-it, removed and cleaned fuel injectors, new fuel pump,fuel relay. The computer shows no codes, the map sensor is fine, the scope does not pick up the miss , but it is there. We are a dead end any ideas would be appreciated.
Too bad I can not drive the cobra every day to work.
Any help or direction would be appreciated.

thanks


Rich

[PSB]

Could be a bad plug wire - especially if the miss occurs after warm up.


Pete

[HighPlainsDrifter]

Hi,
The main thing on a Ford is the TPS sensor (black module on trottle body)It has a reostat that turns as you open and close the throttle. It gets worn/dirty inside and gives a false signal to the computer,you'll never find it. Replace it for $30 and your troubles will float away.
Perry.

[racer24]

Perry

Thanks for your input. I took the old bird to a Ford dealer today for a second opinion. Seems that I have a 3% - 10 % loss in the number 4 cyld. Also found out the main bearing is starting to go also. The miss can not be taken care of without extensive work far more than the old girl is worth. Was advised to trade her off and move on. Looking for a newer model now .

Thanks again

Rich

[HighPlainsDrifter]

Rich,
10% is normal wear for an older motor,hell 3% is normal for a mass produced engine! I'd take what the Ford mechanic said with a little suspicion. There are 2 ways to tell if a bearing is worn; 1 - is take a sample of oil and send it out to a lab to get anilized for what metal particles are in it. 2 - Take the motor apart and main and rod bearing out and inspect them. There is no other way to tell if the bearings are worn unless it's hammering like a sledge hammer.
Good Luck,
Perry.

[rlearp]

I'd just drive the thing until the bearing fails. I've had cars with rod bearings that woke the dead on startup but still got another 58k and 4 years of use out of the car before they finally went. Use it up, don't ditch it before its' time.

R