barke32

I just bought a 1993 SC400 with 94k miles that had dealer service every 10k miles (at least). The person I got it from was having a gasket/o-ring replaced on the Transmission the day before I picked the car up because "they had noticed a small fluid leak". At that time, they were supposed to do a complete filter and fluid change. I drove the car before the work and noticed nothing wrong with the Trans. On the way home after purchase, I noticed the Trans staying in gear much longer than it should with a clunk when it finally shifted (mostly under harder acceleration, shifts fairly normal under light accel). After a couple of starts and stops, the Check Engine light came on and I noticed excessive smell from the exhaust. I'm thinking O2 sensor now. My question is: can a bad O2 sensor (or other 'Check Engine' related sensor) cause the transmission to stay in gear too long. Any other ideas? If the service could have caused the problem (it WASN'T done at the dealer) I can take it back to them on the sellers dime. If it is sensor related I'll spring for it myself. Any ideas would be helpful..

Overclocker

Howdy, and welcome to ClubLexus!


Not sure on the O2 sensor, but I can almost guarantee I know why you get the clunk. Our tranmissions *MUST* have toyota I-V fluid, nothing else works properly.

If it didn't go to a Lexus service center , they didn't use the proper fluid. I'd try and get it drained/flushed and filled with the good stuff.

Overclocker

Mreald

With out a doubt I would make sure that they used the Toyota Tranny fluid. From what you described it sounds as if they did not. If they didn't then I wouldn't wait too long to have it Power Flushed and the correct fuid put in.

For the check engine light.....don't know.....might have the dealer read the code to see whats up and go from there.

Good luck and let us know how it goes.....

Brian

London Bill

If the box has issues it has default "get you home mode", this could be why it is not changing as you would expect, the diag codes should reveal what it at fault - i hope it's not serious.

SCV8

Sounds like either the wrong fluid,most likely,or possibly just not enough fluid.
I'd go and ask them just what they put in there(show me the bottle please),and if it's not a white painted steel,rectangular,gal sized can w/Japanese writing on it,then something's wrong and you'll need to do a totall flush,or else suffer the premature death of an extremely expensive trans.

barke32

First, I really do appreciate the response. This is a great board for a great car! I've been traveling so just getting back to deal with this. It seems that there is a throttle pressure setting that is used to calculate the shift points. At least that is what the Amaco tech said (where the former owner took it). They took the car in and had it back to me in about 2 hours. Now the car shifts very close to what I'd term "normal". It's shifting through all four gears, under normal acceleration, before 40 mph and ~2200 RPMs, but shifts fine under harder acceleration. I'm going to take it to the Lexus dealer to address the Check Engine light and will have them do a proper adjustment. I'll be sure to share any information I get with everyone.

Thanks again guys!