Speedometer/Transmission Related(?) Problem

I have a 1994 Buick Century wagon w/6cyl engine. The car has 47,000 on it and up until last week ran perfectly. Then I noticed that the speedo was acting erratically, jumping back & forth and then completely stopping. Well, now the transmission is acting up. It shifts very hard into 2nd, particularly when cold. After a long run on the hiway, its fine. After stopping at a light, then accelerating, it feels like its starting in 2nd gear. Can the fact that the speedometer cable failed have anything to do with this? Thanks for any input! The Doctor

Reply to
The Doctor
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Not real familiar with that model, but many do use the same sensor for the speedometer that is also used for the tranmission control module. That VSS (vehicle speed sensor) is probably screwed into the back of the speedometer or on the transmission tail housing. If it is on the transmission then the sensor is mostlikely bad. If it is on the back of the speedometer, the cable from the trnsmission that drives it might be the problem

Reply to
Kevin

Sensor is in trans, if the pcm sees no or poor signal it defaults to a 2 or

Reply to
Shep

Thanks for the info! Can you purchase the sensor from Autozone or would this be a GM only part? Thanks!~The Doctor

Reply to
The Doctor

Probably a GM part, but call Autozone first.......you might get lucky.

Reply to
CGBear

Can the fact that the speedometer cable failed

Thanks for any input! The Doctor

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~~RANDOM THOUGHTS~~

There should not be a speedo cable on that car. The speedo is electronic. When it fails, you have 3rd gear starts. The symptoms are exactly those of a bad VSS. A VSS is a Vehical Speed Sensor. It's on the drivers side, top, end of the tranny. It's hard as hell to change without getting burn't sometimes. Sometimes, it's easy to do without getting burn't. Sometimes, changing it, fixes all those same symptoms. Scanning the computer would verify a bad VSS. AutoZonedOut stores can't do it. I can. The VSS is a magnetic driven pickup sensor. The VSS pulses a signal to the computer. The VSS "triggers" off of a cogged gear inside the tranny. Sometimes that ring will get loose. Sometimes this will cause the VSS to give a bad reading. Sometimes this ring must be changed to get a VSS reading. Not always. Not alot. Just sometimes. Though, honestly, rarely so. Your transmission is a 4T60E The 4 stands for 4 gears forward. The "T" stands for transverse. (sideways) The 60 is the series. The "E" is for electronic. I work on trannies. Shep does not. Shep thinks you have a RWD. RWD stands for rear wheel drive. FWD stands for front wheel drive. You have a front wheel drive. Now Shep knows that too.

~~End of Random Thoughts~~

suggestions........... be sure the electricle connector is good and that the wires at the connector are'nt bare and maybe shorting out. It's very common on older vehicals. (heat dries, cracks the insulation) You may be able to fix the problem with some elect. tape.

~:~ Marsh Monster ~:~

Reply to
Marsh Monster

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There is NO tail housing on that transmission.

It is EXTREMELY not probable that ANY vss is screwed into the back of ANY speedometer.

where do you teach, I mean, what State?

I don't want to be hiring anyone you've got so confused that I have to spend an extra year training to forget what you've taught them.

~:~ Marsh Monster ~sips his shroomtea......some do.....some teach~

Reply to
Marsh Monster

I didn't say there was. Never claimed to be familiar with the vehicle in question.

I don't know everything, no one does and neither do you. I'm still learning, you are just being belligerent.. Many GM vehicles in the past did have the VSS on the back of the Speedometer. And many Fords did have it on the transmission. The car in question could even have it in the differential housing or use the wheel speed sensors. Sorry I didn't take the time to list all the possibilities.

I've probably forgotten half of all I ever learned which is probably twice as much as you'll ever know.

There is a waiting list of repair shops wanting to hire more of my graduates so you want have to worry about getting any, and I teach in Louisiana.

Nuff said.

Keep smiling, I am.

Reply to
Kevin

Reply to
Shep

YES!!!! YOU...did say there was. If you can post in open forum that it's "probably" "on the transmission tail housing".......then you damn well DID say the unit had one!!

I don't know everything either. And I'm NOT engaging in being belligerent!!!! I AM however engaged in correcting BAD INFORMATION being given by someone that SHOULD know better than to go posting erroneous info in a usenet forum that could lead a DIY'r to go chasing his head after his arse because of YOUR incorrect info!!!!! Now....call me belligerent if you want, but don't negate the fact that you're the one that posted the mis-information on the topic.

Many GM vehicles in the past did have the

Well......looks like you finally did what you should have done in the first place TEACHER...........you researched the unit enough to learn that the unit you're giving advise on is a FWD vehical. Maybe you should have done that BEFORE you made your first post. OR.....is that how you're teaching your students also.......by guessing? Well......anywhoo...at least NOW you realize it doesn't have a tailhousing. lmao

Maybe you should learn how to research what your spewing forth on!!!!!! I mean.....you are teaching others......it would be good for you to understand that the first step to diagnostics is researching the thing you're fixing to diagnose!!!!!!! Then.....you could start all them wanna be techs out on the right track and they wouldn't turn out like you.....a guess'r. !!!!!!!!!!!!!

And.....as far as to what I know.......well.....it's damn sure obvious that I know more than you on this one stud. I didn't have to research, I knew!!!

Yeah......well......everyone needs trainees. lmao Matter of fact, I've hired a few tech school grads in my time, had a few that were on the apprentice program, where they spent part of their class time at MY shop and recieved course credit for it.

The first thing you have to tell them is....... FORGET everything they taught you.....cuz you need to know how to do it right.!!

fact, not fiction!!!

yep...nuff fer sure.

smiling......hell......rotflmfao

:)

~:~ MarshMonster ~:~

Reply to
Marsh Monster

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