Auto tranny help

ImUrOBGYN

NoNameNomad
Mar 30, 2005
32
0
0
51
Texas
89 Supra auto tranny A430e

Tranny was working great. Pulled motor to rebuild. Reinserted motor. Test drive after everything is done and notice a tranny issue.

Basically, the transmission ignores L and 2, for the most part. Everything works fine; P, R, N, D and O/D. If you put it into L or 2, it may drop down into them a little sooner than if you had it in D, but otherwise, it upshifts like it's in D. It used to hold L/1st, well, for as long as you had it there regardless of rpm or speed. Same with 2nd. Suddenly, it doesn't.

The tranny is throwing no codes.

I disconnected my tranny ecu and it shifts manually with no problems including holding each gear so it shouldn't be a mechanical problem.

Im wondering if it's a solenoid problem. There are 3 solenoids. No. 1, No. 2, and a lock-up solenoid. I cannot currently get under there to check any of them, however.

Any ideas anyone?
 

Nick M

Black Rifles Matter
Sep 9, 2005
8,898
40
48
U.S.
www.ebay.com
If solenoid number 1 fails, number 2 turns on holding drive. Until you unplug the range selector like you did. Make sure you didn't damage a wire in the harness when doing the engine swap.
 

TurboStreetCar

Formerly Nosechunks
Feb 25, 2006
2,778
13
38
Long Island, Ny
Using "L" and "2" requires electrical input to the transmission computer telling it you are selecting "2" or "L".

Basicly putting the shifter in "L" mechanically engages the clutch in First gear so that it doesnt overrun. Trick to this is that the solenoids still need to select first gear for this to work.

In this link to the TSRM EWD you can see the gear selection switch has outputs for "L" and "2".

If the transmission does not downshift to first/second as soon as the shifter lever is shifted to "L" then i would venture to guess its because the transmission computer doesnt know the shifter is there and didnt command the gear change.

I know these facts to be true because im running a SSv4 and when i put the shifter in "L" the transmission still shifts normally. The only difference is when the SSV4 commands first gear, it does not overrun and the engine will slow the car down quite rapidly. If i wired up relays to the gear selection switch to control the solenoids it would downshift to low when the gearshift is shifted to low, rather then when the gear map tells it to.

This may be as simple as forgetting to plug in the gear selection switch but i dont believe the starter would engage then. Im so far from a stock harness im not sure at this point.

Hope thats explains it well enough. If not let me know.