AW4 Help ASAP

[SpikeSpeigel]

Ok... Symtoms: Park= Park (unless placed in park after cycling through gears, then it jumps forward and hit's some osrt of stop). Reverse= nothing, not back, not forward. Neutral= It will go forward like it's in drive for as long as I want. D, 3, 2-1= They all work fine. Also, the engine will not rev over 2700 rpms.

It has been filled with fluid since running about 6 miles with little/no fluid. Tranny fluid leaks out of where the engine/bellhousing meet. Linkage all looks fine and adjusted. No binding it the shift lever.

I'm at the point where unless someone can shed some light on this, I'm going to replace the transmission today. It's the only day I'm going to have to work on it in the next month and I need to get to and from work. I read on here about checking the TCU. How do I test that? I found a tranny for $350. Let me know what you think ASAP please... thanks

[lawsoncl]

You didn't mention what year. The way to test for a TCU or solenoid failure is to unplug the TCU or pull the fuse for it (location depends on year). The tranny should work except you need to manually shift in the forward gears by selecting 1-2,3, or D to select 1st, 3rd, or 4th.

Your problems sound like a shift linkage problem, but the tranny fluid leak is concerning.

[langer1]

Park is strickly mechanical and reverse is also, so that much sounds like linkage.

[SpikeSpeigel]

I've inspected the linkage and it looks fine. I was told by a local mechanic that he heard of a problem exactly like this but couldn't think of what the guy did to fix it. Something like a gear solenoid. I've looked for a similair part with no luck.

Also, I went around the block in it. The drive gears all work fine and it has no problem going over the 2700rpm hump it hits in park. The only problem is I have no reverse and it drives in neutral. Leaking has stopped.

[cal]

I'd check the linkages again. The driving in neutral is suspect..

[87manche]

sounds like reverse is neutral, and neutral is drive, and the lurching is from it moving and dropping into park.

[SpikeSpeigel]

Then how could it shift into 2-1?

[langer1]

You need to go ahead and unplug the TCU and see if everything works manualy. If it does then the TCU is bad.

[SpikeSpeigel]

Haha... Where's the TCU? I don't have my manual... What does it look like?

[langer1]

Haha... Where's the TCU? I don't have my manual... What does it look like?
Under the dash just below the glove box.

[SpikeSpeigel]

Break it down barney style for me. A picture would be awesome. There's alot of wires underneath the glove box. It's a 99'. Do I need to remove any of the plastic molding?

[SpikeSpeigel]

Another thing I discovered. While cruising at say 50mph, if I shift into N it acts as though it really is in neutral. It's only at very slow speeds or at a stop that neutral acts as a drive gear.

Also, with the engine off, in P it won't move, in D it won't move, but in N it'll roll around just like it should. It is only when the engine is running that neutral acts as a drive gear. This is what makes me believe it is an electrical or internal problem and not a linkage issue.

[SpikeSpeigel]

Well... I just took it to what I thought was a good tranny place just to be told what I already know... My tranny won't do anything in reverse and neutral acts like it's a drive gear. Oh and for them to get any better idea of whats wrong, it'll be $350 to take it out, take it apart, and if nothing's wrong, put it back in. If something is wrong, I'll have to pay for parts and labor ontop of the $350. Well, a tranny from the local yard with 50k miles is $350. The only thing is, now the only day I have to do the swap is Sunday. Please help me either find out what's wrong or should I just remove/replace it.

BTW... I haven't found the TCU... I'm an idiot. Can I just unplug it from somewhere on the tranny? Or which fuse is it?

[tgregg]

The TCU is mounted on the lower dash panel on the right under the glove box. Take out the screws from the power dash trim panel all the way across the dash. There is one behind the ash tray also on my 95. The TCU is bolted to the lower trim panel and has the plug on the right side. TCU is a metal box about twice the size of a pack of cigs is about as thick.

[SpikeSpeigel]

Ok... I'm gonna go insane. All I have to work with right now is a multi-tool. I can't get any further than getting the glovebox off. Is there any way to unplug a fuse or straight from the tranny? I didn't see it on any of the fuse diagrams.

[lawsoncl]

The TCU is mounted on the lower dash panel on the right under the glove box. Take out the screws from the power dash trim panel all the way across the dash. There is one behind the ash tray also on my 95. The TCU is bolted to the lower trim panel and has the plug on the right side. TCU is a metal box about twice the size of a pack of cigs is about as thick.

I think I read in another thread that the TCU moved to under the drivers side of the dash in the later years. Not sure what year though. I'm with the others thinking there is a linkage problem. A bad TCU could cause wierdness, but I'm not sure it can cause reverse to act like neutral.

Chock the wheels and set the parking brake, then with the engine off have someone shift through the range of gears while you watch the shift lever on the front drivers side of the tranny. Try moving the lever back and forth with the stick in park - it shouldn't move. If it does pull the plastic bezel around the thifter and check the cable. I'm wondering if the plastic piece isn't broken on one of the ends or perhaps something is bent in the shift detents.

[lawsoncl]

Ok... I'm gonna go insane. All I have to work with right now is a multi-tool. I can't get any further than getting the glovebox off. Is there any way to unplug a fuse or straight from the tranny? I didn't see it on any of the fuse diagrams.


A quick search of the forums reveals that the TCU on 1997 and up is located under the drivers side of the dash near the gas pedal. Same post also indicates there are three fuses in the power dist center under the hood.

[rebelrat]

it sounds lick the forward clutchs are locked in place to me. ive done it on other cars.

[SpikeSpeigel]

Ok... I found and did the TCU test. It works the same with it unplugged and plugged with the exception of me having to manually shift. Oh, and the "check engine" light came on. Something about a torque convertor sensor. I know what the torque convertor is but didn't know it had a sensor. I'm just gonna replace the whole tranny considering the fluid smells super burnt. Thanks for the help. If you can think of any alternatives please let me know. Thanks again...