1995 Metro 4cyl-Auto Trans Problem

[Grub690]

Wondering if anyone has any info on why this auto trans will go into reverse sometimes, and sometimes it won't? I have changed the filter and fluid TWICE in the last three weeks! Also when it doesn't go into reverse, it shifts hard in drive. Is there an electrical, or a sensor problem? Any help would be greatly appreciated! Thanks, Grub.

[hot_sd]

In reverse the sensors do not play a part although it is possible that there is malfunction with the shift switch and the ECM is mistakenly actuating one or both of the shift solenoids when it should not. Quick way to test is to disconnect the shift solenoid connector (round white connector going to the ear right of the trans) and see if the problem still persists. The hard shifting sounds like the problem is internal - could be a sticking shift valve (both 1-2 and 2-3 shift valves are used in R) or a sticking piston in the direct clutch or the first reserve brake. Sticking valves are not too hard to work on as the valve body can be removed from below but servicing the clutches will require the removal and disassembly of the trans.

[Grub690]

Thanks for the reply! I will check the shift solenoid connector first. I don't want to remove the trans., I just put it in last year. (bought the trans on eBay, has been working great up until recently!). I would rather get another vehicle, instead of dumping more and more money into a car that is already 11 years old. I want to keep the car, but I don't have the time or money to keep putting into it. Thanks again, Grub.

[hot_sd]

If the problem is sticking valves or pistons you could try a couple of things that may help before you decide to dump the car. One is to try adding a friction modifer (lubegard red is a good one to use). There is another equivalent one by another manufacturer - cannot remember the name. About $10 but you may have to get it online - I do not think most auto parts stores carry this. The other is to get a auto service place to do a fluid exchange - this may dislodge whatever is causing the sticking. My guess is that the trans was not frequently serviced and some clutch material may be sticking in some places.

Good luck.