[nitehawk92]

This could be a long post. I need help with a problem that seems strange to me. I own a 94 Taurus GL 3.0L Automatic Transmission, 95,000 miles. I took the car to a tranny shop to have it checked out. When driving the car around 15 - 20 MPH and I press on the gas, lightly, it seems like the car up shifts. Then when I release the gas, it is like it kicks back down a gear. Anyway, I took the car to the shop, and the tranny guy asked me if my engine light was on, because the engine could cause problems that might seem to be tranny related. The engine light has never come on in the 3 months I have owned the car. Well it does come on when you turn the key on, but as soon as the car starts, the light goes out. He offered to Diag the car at no charge, so I left the car with him. When I returned he had a list of 5 engine codes, they are as follows.

(129) Insufficient MAF change during Dynamic Response Test
(137) HEGO shows system always rich
(167) Insufficient TP change during Dynamic Response Test
(173) HEGO shows system always rich
(412) Cannot control RPM during KOER high RPM check

The tranny guy did not have any advice other than it is possible one thing could be causing all the codes. He said if after I got the engine problems fixed if I thought there was still a tranny problem to bring it back. So I took the car to AutoZone to have them check the codes, to see if they would have any advice on how to fix the problem. Well when the AZ guy hooked up to the test lead, the only code he got was 111, which appears to be a system normal message. I watched him do it and the only thing he got was 3 single flashes (111). I do not know if the AZ guy didn't do the test right, or what. The tranny guy did not offer to fix the engine problems for me, nor did he try to recommend anybody to do the work. He stood to gain nothing by giving me those codes. In fact he did diag the problem for me at no charge. So he actually lost a few bucks in the process. So I really don’t think the tranny guy was trying to rip me off or anything, so I believe him with those codes.

Do the codes get erased once they have been read remotely? Or did the tranny guy maybe somehow delete the codes in the computer? As far as I know the battery was never disconnected or anything, plus if the problem existed, after I drove the car 10 - 15 miles the codes would probably come back anyway if there was a problem. I do know that there is a problem somewhere. Sometimes when the car idles, the idle speed up and then drops back down, speeds up and drops back...... I saw a thread in the forum about a sensor or something to fix that.

I have seen a lot of good advice through this forum, does anybody have any advice so I do have to pay FORD big bucks to fix the problem? I don’t want to just start replacing sensors till the problem clears that could get expensive. Any suggestions?

 

[93Bull]

This sounds like the infamous VSS (Vehicle Speed Sensor). The sensor itself is around $20 bucks or so from Autozone. Having a local mechanic replace it for you can run anywhere from 75 - 150 bucks. I had mine replaced last year and I only paid $75. Do a search for VSS or vehicle speed sensor for more info. Hope this helps.

 

[maceslin]

Codes stay in the cars computer until they are cleared by a scan tool, disconnecting teh battery for about 30 seconds or the problem is fixed.

As to what casued the coeds to pop I haven't a clue

 

[silvapain]

The guy who pulled the codes could have deleted them by accident. They usually won't pop up again until at least two key cycles after they have been cleared. That is probably why the Autozone guy didn't find the codes.


I would have to suggest that it is the MAF sensor that has gone bad. The MAF along with the VSS controls the shift points, as well as it has a lot to do with the A/F ratio.

You can go to a junkyard and buy a used MAF, or get a new one from the dealer. I am alway leary about getting something so fragile as a MAF from a junkyard, because the Filament can be easily broken.

 

[silvapain]

Oh, and welcome to the TCCA!

I always forget that.