Harsh Engagement Into Reverse When Cold

zupta82 · Post by **zupta82** » 14 Mar 2019, 20:06

Hello everyone I have a 1995 Volvo 960 with 187K miles. In the past month I have been noticing that when cold my transmission has been going into reverse rather hard (As in the car jumps). I always kept up with maintenance and in the past 6 months months I have replaced the (U joints with GKN greasable U joints, New center support with bearing, trans mount, fluid and filter, rear wheel bearings)

Overall, the car shifts beautifully when driving and has alot of power, I just recently had the check engine light come on in over 7 years of ownership. I checked for codes in both A1 and A2 ports and got the following A1( code 142, trans fluid temp sensor shorted) and A2( code 112 ignition module faulty). I wrote the codes down and reset the computer. I drove for about 5 miles and the check engine light came on again. This time I only got the code 112

I was wondering if this is somehow related to the ignition module as if the idle would be slightly higher. I checked the fluid temp sensor with an ohmmeter and read about 572 ohms across the terminals after the car sat for about an hour. I really love this car and we have been thru alot and I want to push its limits to see how long this brick can last.

zupta82 · Post by **zupta82** » 15 Mar 2019, 05:13

Also, I forgot to mention when I changed the fluid the transmission was cold. I used a Miestersatz brand filter, maybe this is a cheap filter that causing a restriction. Im guessing the best bet would be to check for hydraulic line pressure using a gauge.

93Regina · Post by **93Regina** » 15 Mar 2019, 05:20

zupta82 wrote: ↑14 Mar 2019, 20:061995 Volvo 960 ... reverse rather hard (As in the car jumps).A1 and A2 ports and got the following A1( code 142, trans fluid temp sensor shorted) and A2( code 112 ignition module faulty).

I know nothing...is this your Transmission. Auto AW 30-40 If so, they say, "Note that this Mode 1 procedure for code retrieval works only for OBD-I (pre-1996) 960 cars." And when you say, "checked for codes in both A1 and A2 ports," I have no idea what that means in regards to their test procedure.

They also say, "There is also a self-test mode 3 you can enter which is a two man job. One enters the code through the DLC and the other guy is under the car feeling for each solenoid and other device to activate in sequence. Then, you can run through all the gear positions and modes and the DLC will respond with a code that shows the input was good or not. Good for isolating bad components. "

1-1-2 Solenoid S1 short-circuit to battery voltage
1-4-2 Oil temperature sensor short-circuit to ground

zupta82 · Post by **zupta82** » 15 Mar 2019, 06:57

I would have to double check under the car for the nameplate to verify if it is a aw30-40 I’m pretty sure it is that is how I always ordered parts. I retrieved these codes by moving the jumper wire in the diagnostic connector under the hood to each of the individual test ports both A1 and A2 and pushed the button and read the led flash codes. Also what is a DLC, is it like a VADIS system that I can interface with a laptop

93Regina · Post by **93Regina** » 15 Mar 2019, 10:50

zupta82 wrote: ↑15 Mar 2019, 06:57Also what is a DLC

See instructions here

Based upon what I read, their instructions are different from your procedures, if your vehicle is a pre-1996. If true, follow their instructions.

"Note that this Mode 1 procedure for code retrieval works only for OBD-I (pre-1996) 960 cars."

tardcart · Post by **tardcart** » 16 Mar 2019, 06:23

If the idle were above 1000 that would cause a jump into gear. Check the tach, it should be 900. changing fluid is problematic since no dex 3 exists anymore. Only fluids marked "for dex III" which could be anything and may have much harsher cleaners in them the seals in a dex 3 transmission can't handle. People get away with changing 1/3 of the fluid at a time using the newer stuff. If you look back you will see numerous "changed the fluid and now..." posts. I haven't looked but computers for the 960 Are usually cheap on Ebay. that might be the cheapest way to start. same part number of course. Did you get the blinking arrow as well?

zupta82 · Post by **zupta82** » 16 Mar 2019, 08:44

I’m not getting the arrow, I rebuilt the PNP Switch about 3 winters ago with new contacts due to the arrow flashing and have not had any problems. . I’ve always used Valvoline Maxlife full synthetic ATF. I recall the last time I changed my fluid I used an Duralast filter. I guess it always jumped in reverse a little bit maybe because of high miles on drivetrain. During the past month or 2 it has been a lot more pronounced only when cold. I really need my car so I kept driving it. All the shifts are nice and firm with no slipping. I only stopped driving it the past couple of days due to ignition module trouble code keeps coming back after I clear the codes.

zupta82 · Post by **zupta82** » 16 Mar 2019, 08:55

Also , I forgot to mention it idles great with a lot of power and no misfiring.

When I checked for codes in the Transmission diagnostic port I got a code for a fluid temp sensor l . The check engine light was not on during the time when my transmission was acting up. I was wondering if the ignition module is somehow connected to the problem with the transmission

93Regina · Post by **93Regina** » 16 Mar 2019, 21:32

zupta82 wrote: ↑16 Mar 2019, 08:55 got a code

I'd clean all related electrical plugs up with some electrical cleaner.

dm635 · Post by **dm635** » 17 Mar 2019, 06:53

If you find you need a transmission you can have the one I've been saving. But you will have to come pick it up. $0. I'm a little N.E of Louisville. Unable to ship.

If you don't want it this offer is open to anyone needing a transmission. Have to come pick it up, sorry but no shipping.

This came from a car I had to buy for the engine. Drove it around while testing the engine and it worked fine. Was saving it in case I found a 960 needing a transmission. In the process of moving in the next month or two and not taking it with me.