Shifting Problems

Davies14 · October 4, 2015

A couple of months ago my 1994 Lexus ES300 started to have trouble with taking off after being off for awhile. It would stutter shifting wise and the RPMs would jump and fall for about 5 to 10 seconds. Well after a bit that finally stopped happening but instead my car won't shift into 5th (it's an automatic) and drives almost 500 to 800 RPMs higher to go the same speed as before. I was wondering if anyone else has had a problem with this and if so if you know how to fix it. Any help would be greatly appreciated.

gbhrps · October 4, 2015

davies14,

I seem to recall, from posts here over the years, that similar tranny issues were cured by reflashing the computer. Obviously a trip to the dealership would be necessary, as I doubt any other shop will have the software.

Either that or you have faulty shift solenoids, or other internal tranny issues that need addressing.

My advice would be to take to a Lexus dealer for a diagnosis, before anything more causes a more expensive fix. Good Luck!

VBdenny · October 6, 2015

You problem may not be the transmission at all. I would investigate a air leak or dirty throttle body intake. Worked on an 01 Camry today doing the same thing. Upon a look-see I found the casing where the throttle body attaches was cracked. I could easily flex it which was letting in air, causing the computer to think the mixture was lean therefore dumping fuel in causing the engine to stumble due to the wicked rich mixture which tells the transmission not to shift to prevent stalling. Since I didn't have a spare casing on hand, I used Gorilla Tape (strongest tape in the world) to seal the crack. Put a second piece over too. I've got feelers out for a free one but the tape works great. Car runs sweet now. I cleared the 440, 441 and 446 and none have come back however I suspect the charcoal cannister one will.

One problem often shows symptoms in obscure ways. Make sure the engine is truly running correctly before suspecting the transmission. This ain't the old days and the computers control everything now.