Hi all. First post (but I've been lurking a bit, love the site). Couple days ago, the trans (an A340 of some sort, I don't know which one) in my '86 went haywire. As I accelerate from a stop, it shifts up from 1st to OD in about three or four seconds(shift shift shift, that fast), and it won't downshift from OD once it's there, even with the pedal through the floor. I can't tell for sure, but I don't think it comes back to 1 until I come to a stop. It doesn't appear to be slipping, and it moves easily through all gears when I manually select them with the shifter. Trans fluid is full.

I have a copy of the FSM, but I don't recognize this set of symptoms in the troubleshooting guide, and transmissions in general are black magic to me. This trans is new to me, I picked it up last spring on the cheap and I don't know its mileage or history. It's worked great until now.

Any ideas?

 

What size tires?

 

31x10.5, why?

 

Does it do it in the power mode?

 

Yah. I don't have a tach, so I can't be sure, but it doesn't appear to make a difference whether I'm in power or normal mode.

 

Likely culprits, the TPS or the VSS. Check all your electric connections first. You can search and find the test procedure for the TPS, the VSS I'm not sure of the test protocol since it sends out a signal not a voltage.

 

Sorry for the late response. You nailed it, bad connector on the TPS. Thanks for the direction, I would not have thought to go there. Thanks!