There is also a TV (Throttle valve) cable that manually affects when the transmission shifts. It needs to be adjusted correctly for the transmission to shift Up and down when it's supposed to. Getting it wet will not affect it however.

The thing with the TPS is, when the electronics are disabled it can have no effect on shifting. That's why I suggested the test of pulling the fuse. Now if the transmission module was NOT disconnected, then Yes, it could be a bad TPS. As I said before, a Bad TPS should cause other engine problems, like stalling, erratic idle or such.



Once again the first thing that should have been done and none of us mentioned, is to check for trouble codes.
The best way to do it is with a scan tool. You can do it with out one.
Here's how.
Turn the ignition switch ON, OFF, ON, OFF, ON in quick succession then watch the Check Engine light. The two digit Codes are displayed by the light blinking. For instsnce, the code 12 would be displayed as one flash followed by pause followed by two flashes. That means battery has been disconnected within last 50 starts. The codes are separated by a two or three second pause then the next code will be displayed. There is a code for TPS malfunction but I don't remember what it is right now. At the very least you should see code 55. It means End of sequence and will be the last code displayed. If it's the only code shown, it means no trouble codes are set. Unfortunately it Doesn't mean there's nothing wrong. If you successfully pull codes let us know and someone will be glad to tell you what they stand for.

If you want to do you your own repairs, you should start by buying a Manual. Most parts stores have them, Haynes and Chiltons manuals are common. They will tell you how to pull codes and what they mean. They should also have step by step instruction for transmission oil change, TV cable adjustment, Lots of other usefull information. They Don't cost a lot and can answer many questions you may have so you don't have to wait for a reply here. The Information you get from the manual should be considered more reliable that what you get online, though we want to help and do the best we can. A factory Service MAnual is the best source of repair information containing much more complete info on transmissions and other systems but a lot of the info is of no use to the home mechanic unless he/she is planning a complete overhaul. They are much more expensive (around $100US) but can eaisily pay for themselves by saving a trip to the shop.