97 850. Automatic transmission will run fine through all 4 gears and then under load (say 40mph up a hill) it will not downshift. Manual shift to lower gears-no change. I have to pull over and stop and shut the vehicle off and start off again. This is intermitant.
Does the Econ/sport/winter buttons have anything to do with this? I do not know how these work. Any thoughts? Thanks.
Pat

 

DO you see the yellow Arrow light coming up on your dash?
If Yes, then PNP switch could be a culprit.

 

Also try ratcheting your shifter from P all the way to D3 few(8-10) times and see if this helps.

 

No yellow arrow light. Just the check engine light which I will have diagnosed. The vehicle runs fine up and down except when warm going up a hill. It does not want to shift down while giving it the gas pedal. I lay off the pedal and it shifts down. I changed the trans fluid this morning in hopes it may be that simple. It needed a flush. I will run through the shifter as well.

 

CEL turned on may be due to a trouble code in the TCM. If still drivable, visit a local auto parts shop such as AutoZone to have it scanned with an OBD-II scanner, and see what code would come up.

BTW, did you use Dexron-III/Mercon when you flushed the gearbox?


JPN

 

I did use Dextron III on the change, not a flush sorry, I meant to say I removed 4 quarts and added 4. I want to flush next with Mobil 1 ATF now that I've cleaned out a lot of the old dark fluid. Is this advisable to go with a synthetic after having used Dextron III?
I did pull 3 codes...P0171, PO131, PO243. 131- O2 sensor low volts, 171 - system too lean.
243 - Turbo/sup wastegate solenoid A malfunction ??? I'm not sure what that one means.

 

As to the ATF, I would only use a name brand’s basic Dexron-III/Mercon. The AW50-42LE is an extremely sensitive a tranny and can fry if wrong fluid is introduced.This issolely my personal opinion, but synthetic ATF does not seem toprovide any benefit on the AW50-42LE.

I thought the ECU would report tranny-related codes but I was too optimistic. The O2 sensor on 850s seem very sensitive as well, and the only parts I would use is the OEM; Bosch direct fit. System Too Lean may be due to a needed tune-up, the last code may/may not be a problem and I would have them reset and see if the same codes return.

Wait for others’ opinions as well to get better perspectives.

Happy New Year,


JPN

 

Hello Sololight,

My transmission is alsohaving curious issues but I think that I have a handle on it.....I think. And my arrow is flashing.

I recently had to replace my transmisson with a known good used one last month and Im finding that (and to answer your initial question)when it is below a certain temperature the car will start off in Winter Mode .

Winter Mode - This settingwill start thetransmission off in second gear on initial takeoff. Not necessarily an issue with mine as after some driving the transmission warms up and willstart off normally but may be an issue in need of diagnosis for others as Im finding that my issue is almost certainly directly related to the below zero temps that we have been having. This will also light up the arrow on the dash but it should not flash. If you car has Tracs and it is turned onthen it (arrow) may flash when detecting slippage by the front wheels.

Econ - The car will not shift as rapidly/harshly/firmly, in a sence this is an easier or less harshshifting pattern. No where as aggerssive as Sport.

Sport - This is a much more firm/aggressive/harshshifting pattern. Under hard acceleration, the transmission will emmediatly kick down - at least one gear - and then yougot some gitupngoBOYYY.

This is best demonstrated ona highway by getting up to 65kph and accelerating to 110kph. It will seem a little lazy in Econ (green light lit on console above button) mode, but in Sport mode (yellow light lit on console) youll find that the car will down shift hard with a little shoving of you back in the seat and when you begin to level off your speed the car will shift up and may even shift up a second time.

Depending on the grade/angle/steepness of the hill, it may be that the car has decided that it is in the proper gear for the load. Its hard to accelerate up a steep hill and any car will have a hard time with that.

Are you saying that, when going up a hill andstepping on the go pedal,thetransmission will not down shift, but while still on the same hill, this is atthe same time,you lift off the gas pedal and quickly press down again (basically the automatic version of the manual down shift) the transmission does shift down?

If this is the case then, and again this will depend on the grade of the hill, this may help.

When going up a hill the car is already under load and stepping on the gas will only accelerate the carslowly due to already higher than normal rpmsbut if letting off the gas allows for enough of a drop then the transmission thinks that youve leveled off (I hopeI aint too teknakle fer yuh)and gives you what you want. Again, this will depend greatly on the angle of the hill.

[sm=icon_cheers.gif]and Happy New Year

 

Hmmmm... interesting topic, so i dropped by for a read, but now will interject a few of my own experiences. This past summer, my wife and I were late to a wedding here in the Mt. Rainer area of WA. As we neared the last let of our journey, from sea level to about 6000 ft altitude, the 95 T5 wagon would"nt down shift into lower gears. This started when we got off the main highway ( where we had been boosting hard for the last 45 min ) ....and got onto a smaller road which asked for lower speeds. It seemed like i was driving a manual car, when you let off the throttle, it would remain in whatever gear it was in, whereas in an automatic, it would naturally drop down a gear or 2. After a slow taxi around the parking lot, shut off and then back on, it was back normal, but very disconcerting an hour from home.

Part 2, ( same wagon, last week, freezing temps ) My wife has been driving the car ( since we added a 96 R to the mix) She started messing with the Winter mode, and was complaining that it was making noises and the Green light was doing a ton of morse code. ( i wasn't around for any of this ) Seems to be back to normal now though. Anyway, just sharing my experiences and hoping for some shed light.

-grae

 

Great information. It is cold here in Maine, however the problem happened a few times this summer. I will do a trans flush on Monday and then run it during the week. I'll report back status of performance or codes. Perhaps I should dig in the console and replace the E/S/W indicator lamps so they work, also. thanks.

 

Hm, got to use winter mode for the first time in the R today on the way home from work... slipping around in what? MORE snow? geez im tired of this...

 

Exactly how do you use the Winter mode button? Push in? Pull up? No indicator lights or owners manual.....thanks

 

You should just have to push it down once.