90 A140E not shifting

[sanders]

Hello all, new here.
Problem with a 1990 4 cly auto, I was driving home from work the other day and everything was fine, then all of a sudden the trany went in to N and stay there. Fluid level is good, I pulled the cooler line and no fluid is pumping out. Any ideas.

[Doctor J]

Does fluid level goes down while engine is started ;are there any noise from tranny while engine is running?

[sanders]

Fluid level does not change and there is no noticeable noise. Could the shift switch on the front have gone bad?

Thanks for the reply.

J

[Doctor J]

This sounds like pressure loss due to the plugged screen; stuck open pressure regulator or [rare] the front pump is not rotating by the engine.
Drop the pan remove the screen; if it is clean, locate the regulator valve [big one spring loaded and tap its bore with screwdriver handle, this may free the valve].
If there are lot of debris inside the pan and screen is plugged up consider rebuilding in the future; after cleaning the pan and using new screen the transmission still can work.
The front pump is driven via converter hub; On American cars the pump gears can broke but this should create lot of noise; the torque converter is bolted to the flex plate by 6 bolts; I doubt, however that they all can fail at once.
Ps You can also check my thread about "torque converter noise"; it may not help in your case but worth reading!

[sanders]

ok drained pan fluid looks good no visable debries. Dropped tranny TC have fluid in it, pulled pump and all drain holes and ports are clean. Installed tranny and still acts as if its N, no wheel movement when gas is pressed. Also whit gas pressed I can shift from P to low with nothing happing. I wish I would of read your reply about the spring before I did the work. What else do you think. Its almost like no fluid is getting to the pump.

Thanks J

[fredk]

hey doc, ya think something happened in the differential?

[Doctor J]

sanders wrote:"I pulled the cooler line and no fluid is pumping out", in addition if axle or differrential will broke, the tranny will grind when shifting back to park as the input shaft will spin.

[sanders]

Ok guys, I pulled the electronic shifter contol off and cleand/inspected it, it is fine. Pulled the pan and knocked on eveything including the regulator valve. Soungs like the selonoids are working. The fluid looks good screen was clean. The fluid is just not getting pumped through the tranny at all.

Before I pulled the tranny the first time I could get the wheels to spen if I reved the motor up way up and it felt like it was shifting but I had to floor it.

After I dropped the tranny I swapped to another used TC and pulled the pump. After inpecting the pump all the ports and holes where clear and clean.

I put everything back together and now the wheels will not spen at all. When I tach it up the tranny does not do anything. I can shit from P to L when the RPM up.

I am lost. J

[Doctor J]

If there is absolute sure the fluid is NOT pumped, and you refill it correctly, the tranny may have to come out again
You may have take it apart , taking pictures of input shaft, front pump direct clutch and post it here.