Hello- I have a 94 850T automatic and the transmission is acting weird. First thing in the morning when I start the car even after warming up the engine the transmission shifts out of first at 3000rpm, if I push the shifter forward slightly it will shift fine. It shifts/drives great the rest of the day even after extended stops. I replaced the atf fluid the recommended dex/merc stuff following the three time strategy and the transmission sounds great now but it still does this just about every morning.

I think in sport it shifted fine first thing, I read the other posts on this and I have no codes or a warning light or the flashing arrow. I have noticed that it will also shift fine in position 3 but the arrow will not come on unless i pull back on the shifter lightly, weird. I was reading that there are two adjustment on the shifter that can be done, but I have never done it, n/d and 3/1.

What is the exact purpose of the PNP switch and will it affect the shifting of the car, from what I have read the ecu controls the solenoids and thus the shifting. Sometimes I also have to push the shifter forward in park a little or it will not start.

I also noticed that when it rains and only when it rains there is a weird thumping noise that happens when i am slowing down to a stop it it sounds like it is coming from the area of the transmission under my feet, can feel it on the shifter. when it is dry out it never happens not a single vibration or thump, weird.

Any ideas out there???

 

Sounds like a misadjusted PNP or a bad PNP. The PNP tells the ECU and TCU what gear the transmission is in. Also by your note that sometimes you have to push the shifter foward to get it to start leads to a PNP.

 

Tech-

Thanks for the response.

I was wondering how to realign or readjust the PNP?

 

also the chilton manual says the nuetral switch is on the shifter rod not the transmission, which one should I replace or check?

 

The one you need is the device on the tranny; see attached. Inspecting the throttle cable is not a bad idea, though it may not have anything to do with the trouble.


JPN

 

There is supposed to be a special tool to adjust it.
But I forget at the moment but I had looked at the wiring diagram and found the 2 wires for the switch. Then used my meter on Ohms and set it to beep when it was in neutral and park. Then adjusted to get it right.
It might be blue and red on the PNP side.

There is no switch on the shifter for it.