What's wrong with my tranny?
 

The car is an auto 90 gxe with 174k. The problems started at around 170k. At first it had serious problems going in reverse and idled roughly. Took it in to our regular mechanic and he said it needed a rebuild, but for $2500. Said no way, took it back and the problem magically disappeared. Through the next couple thousand miles the problems came back and went away, including 1st gear not catching when first put into drive.

Now the problem is that it stalls out when I come to a stop. If I put it in neutral before I stop the engine won't stall but I have to give it some gas before going back into Drive so I get treated with a lovely forceful jerk. This problem of course also goes away and comes back when it wants to.

So has anyone else had these problems and is a full rebuild the only solution? I took it to Cottman's last weekend and they said they couldn't find anything wrong with it, they even held it a day extra to retest it after I explained the symptons. Again nothing found.

One mechanic I talked to said it might just be a bad sensor, could this possibly (and hopefully) be true? Thanks for any help.

anyone? :bawling:

Search for ignition coils, MAFS and Oxygen sensor.

Re: What's wrong with my tranny?
 

You can find some good deals on transmissions on ebay. Way less than 2.5K

Re: Re: What's wrong with my tranny?
 

Doesn't sound like a transmission problem, at least to me.

Time to break out a multimeter and factory service manual and test a couple of components such as the mass air sensor, throttle position sensor, fuel injectors, auxiliary air control. etc etc etc. If you know how to work a multimeter you can save yourself alot of money by disgnosing the problem yourself, the factory service manual outlines the procedure to test each of these components.

BTW, in the meantime, avoid putting the car into drive while giving it gas, at 170K i would be pampering it as much as possible, not hearing it go THUD!

good luck.

Well, from what I read, if you do actually have tranny woes, your car dies because there's something wrong with the overdrive sensor (if you leave O/D off when you do city driving).
What I have learned is that your OD sensor is not kicking the tranny out of OD when you are coming to a stop and reaching a stop. It's much like how a manual transmission would kill the engine when the driver leaves the engine in 5th gear and then coming to a stop, without depressing the clutch.

Maybe not much help, but might give you an idea to what's goin' on down there so when you approach the mechanic, you won't end up purchasing a rebuilt engine, tranny, and whatever might NOT be wrong.

Good luck.

Re: What's wrong with my tranny?
 

How long do you warm your car up before taking off? Is it cold where you live right now? I had the same problem and the here's the deal. Our transmissions lock up the torque convertor in fourth gear to provide a direct link between the engine and the transmission and therefore give better highway mileage. The only problem is that if the fluid in the torque convertor is cold and sludgy (time for a tranny fluid flush, when was your last one?) the old torque convertor does not want to disengage. The basic job of a torque convertor (other than to convert the torque of the crankshaft to fluid pressure and then back to torque in the driveshafts) is to allow the engine to idle without depressing a clutch when you come to a stop. When the torque convertor is old and tired, it does not want to disengage and as a result the engine battles the transmission. It is essentially the same as rolling to a stop in a manual car and not depressing the clutch (ie. stall). The simplest solution I found was to let the car and especially the transmission warm up before driving anywhere. One easy way to tell, at least for me, as to when it is safe to drive involves the engine idle speed. Our cars, and most cars, are equipped with a cold start loop. Basically, if it's cold outside, the engine will idle at a higher RPM in order to speed up the warming of the engine and provide more heat for the HVAC system quicker. This cold start loop is approximately a minute or two long, so it's not too long to wait. Just watch the RPM's and don't put the car into gear before the RPM's drop from around 1200 RPM to about 800RPM. Once you are out of the cold start loop, slowly move the gear selector through each gear, allowing the selector to rest in each position. This moves the transmission fluid throughout the gear box and gets the fluid heated to an extent. In the short run, this will work wonders for your transmission and for your sanity. In the long run, your transmission will have to be replaced. It's just a fact about the cars. 174K miles is really good for the original transmission (I have 156,000 on mine and will probably rebuild it this summer). I would also suggest some driving tips and general tips for the longevity of your transmission. First, get a full transmission fluid flush. Don't simply replace the fluid yourself. You can only drain bout 5/8 of the fluid in your transmission without a special machine. The special machine actually runs about 4 times the amount of fluid through your transmission in order to fully flush it out and replace all the old fluid with new fluid. If your transmission fluid is brown, has metal particles or any other particles in it, or smells burnt, you desperately need to have the fluid flushed. Also check the level of the fluid. Remember that too much fluid is just as bad as too little. Secondly, if you aren't going above 40MPH, turn off the overdrive switch. This prohibits the transmission from switching into overdrive (fourth gear) and locking up the torque convertor. This will preserve the clutch bands in your transmission (the main source of failure in our transmissions) and your torque convertor (which is old and decrepit). And finally, buy a transmission cooler from pep boys or autozone. The Haynes models are great and the smallest size they have will generally work. Don't forget to add more fluid as the transmission cooler increases the capacity of your transmission. The number one cause of automatic transmission failures is overheating of the transmission fluid which causes a change in viscocity and a breakdown of the fluid's protective properties. Once the fluid has been broken down, clutch packets and the other delicate parts of the automatic transmission are exposed to damaging forces and generally fail. I hope all of this has been helpful and let me know how my tips work out for you. Have a great day.