Possible Transmission problem with my 95 T-Bird

[poehitman]

Ok, here's the deal. I keep having this problem with my Bird that I can't seem to figure out, but I think I might have it pinned down. At different points between 30 and 60mph, I get a heavy vibration that lasts between 2 and 4 seconds. The best way I heard it described is that it feels like you're driving over railroad tracks. Also, when my car is idiling, or I'm backing up, the car vibrates heavily and feels like it will stall, but it never does. It does all this whether the OD is on or off.

I think it could be something called the Manual Lever Position Sensor, but no auto parts store seems to know of this part. My car is a 1995 Thunderbird LX with the 3.8L V6 engine and the Auto Trans. Any help is appreciated.

[Rolling-Thunder]

Doesn't sound like an MLPS problem.
More than likely, the vibration while driving is Torque Converter shudder. Ford's fix for this is MerconV traany fluid. All the old fluid (13qts.), has to be flushed out first.

The rough idle could be a dirty IAC valve, dirty plugs, or a defective spark plug wire.

visit www.tccoa.com, and use the search feature in the Forums section.

[poehitman]

Not sure what an IAC valve is, but I replaced the spark plugs and the wires and it just continued to get worse, so Iknow it's not the plugs or the wires.

I found this on the internet and it sounded EXACTLY like the problem I'm having.

Always run a scanner first to see if a sensor is causing your problem. I recommend that you change the transmission fluid about every 12,000 to 15,000 miles. These transmissions can develop a symptom called torque converter chatter. The vehicle feels like you are running over railroad tracks when the torque converter locks up between 35-50 miles per hour. There are also valve body recalibration kits you can have installed to help prevent this before it occurs, or while your transmission is being rebuilt. The manual lever position sensors like to go bad on vehicles with these transmissions.

[Rolling-Thunder]

Torque converter shudder is what I mentioned in my above post. MerconV is the fix.

Do not buy any valve body recalibration kits, without knowing what they do exactly.
Most "shift kits" will hurt your tranny.

Your MLPS, as I mentioned above, is probably OK. They did improve the design of them in 96 and up tranny's

LASTLY, spend some time over at www.tccoa.com

In the Technical Articles, transmission section, read the first article. It was written by one of the engineer's that designed the transmission in our cars.

And lastly, don't mess with the tranny till you've read up on it. I have 193,500 miles on mine, and it has never needed a rebuild.

Good Luck with yours !!


EDIT: The IAC valve controls your idle rpm only. It can become dirty with time. They can be cleaned, but it is not recommended by Ford. They only advise replacing them.

TCCoA has pictures of it posted in the forums section. Use the search feature there.

Another rough running culprit can be the MAF sensor. That can be cleaned, with careful study beforehand, at TCCoA.

Hope this helps............

[ 10-02-2003: Message edited by: Rolling-Thunder ]

[fordman49450]

well being a trans tech at a Ford Dealership, it sounds like a TCC shudder. I have a 95% success rate by draining the fluid, including the torque converter, and filling with the new Mercon V fluid... give it a shot, I think it will fix your problem.. ;)

[poehitman]

Anyone know how much a Idle Air Control sensor or a Mass Air Flow Sensor costs for my car? Ballpark?

[poehitman]

One more thing. When you pay these auto repair shops for a Transmission flush, does their price usually include the 13.2 qts of Mercon V fluid or am I gonna end up paying an extra $30-$40 for that? Plus, I don't want to sound like an idiot when I ask for this fluid. Is is Mercon "V" as in the letter "V" or is it like the roman numeral making it Mercon 5 fluid?

[ 10-14-2003: Message edited by: poehitman ]

[Rolling-Thunder]

MerconV is called MerconV on the label.

It costs more than the older Mercon fluid, so there may be an extra charge added to the bill. It is important that they get all of the old fluid out, including what is still in the radiator and the lines connecting it to the tranny.

[Rolling-Thunder]

The IAC will be around $60, and the MAF sensor will be arouind $150.

Do not buy an aftermarket or Autozone Maf.
They are not as good as Ford's

Call Dan Newman at Joe Cooper Ford
1-800-266-6049. He will give you the best price. Be sure to visit www.tccoa.com
Dan is talked about alot there.

[fordman49450]

Mercon V is normally referred to as Mercon 5

[Rolling-Thunder]

LOL

I can't believe I mis-read his question......lol

Yes, it is pronounced Mercon Five as fordman correctly states.