bjkilpa

1991 lS400 186,000, its amazing how reliable it is, just cleaned the radiator last weekend. it had 16 years of filth in the fins.

on my 1991 LS I had a bad Alternator causing a Howling/roaring/screacing (i cannot remember) I originally thought it was the power stearing pump, but turned out to be the Alernator bearings.

yea let me know, I love fixing things myself. the dealer would have charged 1K to fix the solenoid. I hope it fixes yours(jimancini) also.

Well just to provide feedback, after replaceing solenoid number 2. the car shifts properly now. Not sure the problem Mikedudd is having, my car does not have the TRAC system.

If your car is shifting from first to Fourth than its Solenoid number 2 that will not turn on(sticks in the off position), and therefore the only thing the transmission can think of doing is turn off solenoid number 1 which puts it into 4th gear (failsafe mode). if solenoid number one is bad, then it would go into first to second gear or third and fourth, depending on if solenoid One is stuck in on or off. The shop manual explains all the *BLEEP*ing paterns and how it would act if a solenoid fails. This may be more detail than you need :-) You should down load the codes from transmission and it should tell you which is failing, the shop manual will tell you how, to short the diag port to get the codes.

I just replaced the Solenoid number 2 and while up on jack stands, it shifted fine through all gears, I am glad it didnt fall off the jack stands and take off into my kitchen :-). I sent my climate control module into Jim Walker to replace the LCD, once that is back and installed Ill do the full test, to see if it fixed the first to fourth shift problem. I bet jjmancini has a bad solenoid number 2 also. Part number 85420-50020 was the correct one. you can get it from irontoad.com for 155 bucks. That part works for solenoid number one or two. Ill keep you posted.

Good advise! I removed solenoid number 2 and checked the resistance between the solenoid connector and the solenoid base and it is out of spec. The repair maual says it should be between 12-15 ohms this was 21. I ordered one from Irontoad.com for $155.00. Ill put it in next week and see how it works.

Isnt the internet great!! I just found the Part number to solenoid number 2 its (8542050020)(same part number as solenoid number1) at lexus its $229.00 list and toyota has the same part and its $199.00. I will try and replace it this weekend and see if it solves the problem on my car. If you have the repair Manual, you can get the error codes from the transmission and see if you have the identical problem. On yours it could be solenoid number 1 or Number 2.

I Just got a breakthrough. I Have the same problem, and I just checked the codes on the diagnostic port for the transmission and I have a Code 63. This means that solenoid valve number 2 has a short circuit or Open. When this happens the transmission goes into Fail safe function and directly shifts into Overdrive (4th gear). I bet I need to replace solenoid number 2, the electrical cables or the ECU. I an sure the solenoid itself is bad.

This is where I need help also, I have the repair manuals so I can see if there are any codes that the transmission is putting out. I can only guess that the throttle position sensor or other such as the temperature sensor may be malfunctioning, or the transmission computer. Ill do some more homework to see if I can isolate the problem.

I have the same problem with my 1991 LS 178,000 miles. Its intermintent and only does it when its real Hot out (90degrees) and the car is fully warmed up. I also just replaced the transmission fluid and the transmission filter. However, I used Dextron III fluid( the valvoline website says the dextron III is fine for this car, but not totally sure). What I think is happening is the transmission is shifting from first gear directly into 4th gear instead of going to second and third.. I am assuming the computer must be gettting bad signals from some sensor to cause this to happen, or a problem with the valve body. I need help on this issue also, I dont want to pay the Dealer more than the car is worth to get it fixed.