won't shift to 2nd when cold

[98postal]

Hi , I just bought a 98 3.0L from the post office , only 42k so I thought it would run fine, but It wont shift into second for the first few blocks, it just winds out like it's in neutral, over the next few blocks as I stop and start up again it gradually starts to shift sooner and easier until running normal and smooth all day long,but if left sitting for a few hours, same story. code P0708 shows up "Transmission Range Sensor Circuit High Input". Also If I shift to 2nd manualy it goes , then back to drive it works after that. Fluid level is fine. any advice? Is it just the TRS?

[9postal8]

I'm new at this , is there anyone out there ? I replaced the TRS based on suggestions from those on this site, from what I read , but the problem persists, does it take time to re-train the Computer, doI have to reset the PCM? Any one? the van works great after the first 4-5 blocks , I changed the fliud and filter ! no metal on the magnet. Is it another module?

[wiswind]

You might check to see if you still get any code(s).
There is a temperature sensor inside the transmission.....but one would think that a problem with that would give you a code also.

[9postal8]

thanks, no check engine light yet! could codes show up without turning it on?

[glennet404]

Hello-

Question - or point of clarification.

When you start off with the shifter in 1st gear from a cold start - can you shift into 2nd gear manually ??

If this is so - then it probably is the 1st gear shift module. If you changed the fluid and filter - you probably could tackle the shift module as well.

Glenn

[9postal8]

It won't let me shift to second manualy, from first when it's cold, last night I even tried to start in second-which worked, and then to drive and it still did not want to shift to second.. until warmed up-2-3 blocks? really wierd. like I said after this it shifts like a dream, seems like it would have to be some kind of electronic relay problem right? I don't know what to try next. if I unplug the battery for 15 min. to reset the computer might this help? will it cause any other problems? Help! The postal service said there were no known problems , I think I just got screwed.

[9postal8]

PS. I just changed the fluid , are these shift modules supper easy to get to?

[glennet404]

Based on this new information I don't think it's the shift solenoid - but if you decide to replace it - it's about a $25.00 item and takes a couple hours to replace. If you look inside the engine compartment on the drivers side - look down at the transmission in about the area between the brake cylinder and battery - you'll see a square pan on the side of the transmission. Beneath this pan are the shift modules and valve body assembly. Like I said - I don't think it's the solenoid - but if you want to try it - its worth a shot.

It sounds like one of two things:
1- The transmission is unable to maintain pressure until warm - or-
2- Something in the band assembly or valve body is stuck - until the heated transmission fluid frees it.

If its the pressure problem - them its either a bad torque converter or transmission pump. If its one of these two items - they would eventually fail.

If its the issue of something in the valve body - like a valve or check ball being stuck - you may be able to free it with an additive. I would be leaning toward this - 42K miles on a 98 is not a lot of miles - bet the transmission fluid wasn't changed regularly - and the vehicle may have even sat for a period of time. When this happens the older Mercon type transmission fluids can turn into something like a varnish and coat the internal components. When this happens - things get stuck. While I'm not generally a big advocate of additives - this may be a case where a transmission additive may be of some benefit. If you search this forum you'll see additives discussed at length. For what it's worth - a few years back I had a diesel Mercedes that would not shift past 1st gear. I got turned onto a product called Trans-X. It worked like a champ - and I probably got another 10K miles off that tranny before I finally sold the vehicle.

If you go the additive route - while it's a very remote possibility - you could end up doing more harm than good - so you really need to think this one through before you go with additives - and don't say you weren't warned.

So - if were taking opinions - I would probably go with a quality additive first. If that didn't work I'd probably tackle the shift solenoid - and if that didn't work I'd probably just drive the thing until the transmission gave out.

Good Luck-
Glenn

[9postal8]

Thanks glenn!