1991 Camry Transmission or Electrical?

[John Martens]

My father has a 1991 4 cyl Camry A/T with 255,000 km on it.

Today he stopped at the stoplight and when he went to accelerate, the engine would just rev like you have it in neutral, no forward motion. He turned off the ignition, turned it back on again within five seconds, put it in drive and drove away with no problems. Same thing happened every time he stopped the car at a light or in traffic. No odd noises heard, O/D light did not light up. Haven't had chance yet to pull codes. I haven't seen this anywhere else on the board. Suggestions?

John

[Tommy]

couldnt tell ya what the problem is, but the transmission is electronically controlled.

[toyomoho]

I think the ECM controls the shifting points and O/D engagement. Not the R or D engagement. Next time it happens see if the problem is in all forward gears and reverse.

Might be a manual shift valve. The link below provides access to the service manual. There is a good section on transmission diagnoses.

http://oregonstate.edu/~tongt/camry

[John Martens]

Originally Posted by toyomoho

I think the ECM controls the shifting points and O/D engagement. Not the R or D engagement. Next time it happens see if the problem is in all forward gears and reverse.

Might be a manual shift valve. The link below provides access to the service manual. There is a good section on transmission diagnoses.

http://oregonstate.edu/~tongt/camry

He says it has no motion in any gear until he shuts it off and restarts it. Then it will be ok until the vehicle comes to a stop again. I've got the entire repair manual saved on a CD so I'll start going through the troubleshooting guide.

Thanks

[Kingdom934]

Try check the fuse box inside the car (driver kick panel) to see if anything is blown.

I have tranny issues with a '85 Camry, seems to be a electrical issue as it keeps blowing out the ECT-IG. Lots of reving and little go in any gear except 'L' and 'R' from a stop position.

[Doctor J]

The described defect is of mechanical nature.
The proper way to check it is to hook up the pressure gage to the transmission and check for line pressure. The home remedy is to clean the screen, but the problem is believed to be related to the to the worn sealing rings on the transmission front pump or stuck open pressure control valve.
Is fluid aerated (has bubbles of air in it)?
The dirty screen is usually causing slippage and judder at take off cold which improves as a line pressure builds up.
But drop the pan and clean the screen first. Let me know if there any metal is in the pan.

[John Martens]

Checked the codes from the transmission, got no errors.Drove it around for a bit, and only after the engine was warm the problems began to manifest....you'd be driving, and then suddenly hear the engine racing because it wasn't transferring the power to the wheels. Pull over and turn it off..restart it and then it would be good for a mile or so.Checked the dipstick, and the fluid IS darker and does smell burned. I'd love to drop the pan and check for metal shavings, but dad says he'll just tow the car to a transmission shop on Monday...I'll go with him and give you all a update then.Thanks for the help.

[Kep]

Ohhh, I see dollar signs. If they suggest that the transmission needs to be rebuilt (which they always seem to do) I would definitely get some estimates on replacing the transmission instead. I am not a fan of rebuilt transmissions. Too much chance for human error. Even a used one might be better than rebuilding this one.

Just out of curiosity, how often has he changed the transmission fluid?

With the transmission failing as it is, you might want to consider a power flush. I hardly ever recommend them but if he is willing to replace/rebuild the transmission anyway it won't be a loss if it doesn't work and it might just clean out some crud that is blocking an important passage.

You might also start researching the various additives. If the service cost is more than he wants to pay there are all sorts of additives out there. They make outlandish claims but you may find one that helps his situation. Again, these are kind of last resort attempts. If they don't work or if they make the problem worse it doesn't matter because you were going to park the car or replace the tranny anyway.

Luck,
Kep

[Doctor J]

Trans-X was the good additive. If the hard (metal) parts are worn or damaged, it is less expensive to install used japanese transmission.

[toyomoho]

Again I would down load the transmission service info and do some roads testing. The service manual has a lot of good info. The trans has about 4 electric solenoids that control shifting and OD on/off, plus a few other hydraulic valves. Most of these can be accessed without pulling out the trans. Could be just a sticking valve.

[Doctor J]

A140e transaxle has 2 shift and one lock up solenoid. Sticking valve will cause non-shift condition. The loss of line pressure causes tranny to fall out of gear.

[ironpig]

It definitely sounds like a shift solenoid. They are fairly easy to replace just a little spendy.

[Doctor J]

When shift solenoid is plugged, the transmission will lose two gears, but the car will move.
The forward, reverse and low are controlled by manual valve.

[John Martens]

Ok...

Pulled the tranny pan today...minor metal flakes, some metal 'flour' stuck to magnets.

Replaced the filter while I was in there..

Reinstalled the pan, dropped the car down, and put 2.5 litres of ATF in the filler tube. (as per repair manual)

Started it up, ran it through the gears and checked it again while it was idling. Mark came just below cold. Added a little more ATF.

Drove it around. Works great in all forward gears, but reverse had no guts. Would drop into reverse no problems but would hardly move at all with revving of engine. Added a bit more ATF. Drove around again. Now better speed in reverse. But now has odd 'scraping/grinding' sound coming from tranny. But only in reverse. All other gears it is silent.

[Tommy]

reverse and the forward gears are usually the first to go - time to start transmission shopping, it doesnt get any better from here out.