QuestionThanks for the reply, I've since put about 200 miles on the car since the shop last had it. They flushed the old tranny fluid and also put in an additive that they say they've had excellent luck with. It actually seems to be helping. They seemed to think there was a valve sticking in the valve body, and this "might" help. Like I said, it seems to be, but I would like my car back to normal. It was great until this came up out of nowhere. Does this additive helping give credence to the sticking or hanging valve you mention? If so what would you recommend? They think a cleaning of the valve body may be in order. Also it seems to be fine when cold now, and acting up after its warmed up. I'm completely confused since this is the opposite of what it did when this all started. Thanks alot, this site is great!
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Hi, I have a 1998 mercury sable (135k). It stalls or wants to stall when put in gear, reverse or drive. It idles perfect in park and neutral, and drives down the road fine. When I come to a stop is the problem. It bucks and wants to stall, or will stall. I have to throw it in neutral. I took it to a shop and they got a code for the TCC. They replaced it and said it was fine. When I picked it up it was doing the same thing it was when I dropped it off. The mechanic drove it around a bit, it was trying to die, then it was fine. I've been driving it for the last few days now, and sometimes its fine for a while and sometimes it is almost undriveable (have to put it in neutral and at stop signs, then throw in drive and slam the gas), the shop is stumped as to what is going on. My service engine light is on again and the o/d off light blinks sometimes also. I would really really appreciate any insight into this! Thanks alot!
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Hi Burt,
The reason he thought it was fine is because torque converter lock up only happens when your car is at full operating temperature. Won't do it cold. He didn't test drive it long enough. This is being cause by one of three areas. First, it is probably leaking from the charge area to the converter keeping it on once lock up is called for. Second, a valve in the valve body is hanging leaving lock up on, or it's a bad torque converter. Do you have a Cottman near by? (cottman.com or try aamco.com if not) An independent shop will not have access to this information. If I had the actual code number I could be more precise in which area we need to look in. I suggest having Cottman or Aamco transmission perform their free diagnostic service.
AnswerSorry to say Burt, but it is only temporary. Like nasal spray is to a head cold. In fact, and this has been mentioned by myself numerous times to transmission questions, the fluid being changed has doomed that transmission. Is this a transmission shop or general repair? Changing the fluid in a car with 135,000 is, well not a good practice. Transmission fluid develops a condition we call varnishing. Once it has varnish in the fluid, the brown looking stuff, it must stay there. If you change the fluid and especially flush the transmission, this varnish will no longer be holding things together and your car will start to slip in about two weeks. I have seen it so bad the car didn't back of the lift after the flush. I have been strictly transmissions for 12 years, I work on about 100 cars a month. Half of the overhauls we do are on cars that had fluid changed or flushed within 2 weeks to 2 months. A good transmission shop would have known better than to do this to you and I recently wrote a giant answer to someone asking about additives and synthetics. We use an additive, Lube Guard, to change the structure of fluid for different vehicles. Some need slipperier fluid than others. So instead of stocking 40 different kinds of fluid, we "mix" what we need. But most importantly, if it was supposed to be there, it would already be there (additives and synthetics). We save old fluid from the car we are servicing if we have to drop the pan to get to solenoids and put it back in. Because we know what will happen by changing even a few quarts. I want you and our readers to be careful with transmissions, I hate to see someone think they are doing the right thing and then cause themselves a headache.
