Calbha

i have a beautiful 1990 v8 quattro 3.6 and have need only 2 major things done to it in the year ive owned it. 1. the power steering rack and 2. the rear main seal.

after my friend did the rear main seal for me it drove fine for a while till one day the car refused to leave sports mode.....thats right its stuck in sports mode, (not limp mode) will not go to economic or manual and the car refuses to shift into 4th gear till 120 mph at least. so im guessing its the switch. i find a wonderful gentleman in california to sell me the switch outta a tree smashed 3.6 v8 quattro for 30 dollars! ($300 from audi with a 6 month wait) not to mention he sent me the transmission computer for free! so i plug in the new switch and it is still stuck in sports....plug in new computer and its still stuck in sports my friend and i think it might be a white looking box with a fat cable on the drivers side of the transmission right above the shift link a smidget to the front of the car but i dont know what its called or where i can find one for a decent price hell i dont even know if thats the problem! please help im driving everywhere going 50mph at 3k rpms watching gas just flow out the tail pipe! (not literally but you know what i mean)

Adam Mowafy

I'll look. Otherwise if you end up needing a trans, I have a good used one for sale.

NeatV8Man

Please somebody help, I am having the same issue except it really only happens until car is at normal temp, or occasionally when I slam it to the floor it just stays in sport or 3rd. The switch is pointless when this happens and does nothing. I even dared to move the lever through all 4 (D 3 2 1) while going 60 mph and nothing happened, just stayed in 3rd. Now on the other hand if I pull over when this happens and turn off the car then restart I can drive off in economy just fine the rest of the day. I have also been noticing economy shifting is getting harder when it shift or downshifts. RPM in springfield VA just did filter/flush replace with Audi fluids for $600 3 weeks ago. It was perfect for a week then this crap. Please help!

AK_92_V8

Like th idiot I am i messed with the tcu thinking it was the ecu from some ****ty instruction..but anywho. It may be low or overfilled on fluid. The car doesn't like to be at the wrong levels. It will cause the car to go into limp mode which is where the car only has use of park reverse and 3rd gear. Maybe you have a bad tcu who knows at this point. If you don;t have a dip stick for the tranny then I would go and buy one because they will save you money in the long run. I don't know where to get it cause my car came with one. When you turn the car off and restart it the ecu gets reset and that could be the cause for the differences. Also in limp mode the 3 modes don't work. the gear select led will be lit up. If you put it into manual mode is there a yellow M on the led readout for gears?

NeatV8Man

Yes the M comes on. What you describe is exactly what I have happening. This morning it immediately went into 3rd and stayed there. Came to a light and turn off the engine, back on and was fine until about 30mph where a hard shift was felt and back into 3rd. No upshift or down from there on. Got off I95 (did 60 little above 3k the whole 6 miles) again turn car off restart and was fine except some rough shifts all the way to work (20 miles or so) When I had my trans filter/flush/refill service the car was great and smooth for about 2 weeks, now it is so frustrating. I have a dipstick for the trans on order. I paid way to much $$ to find out they refilled improperly, So I am excited to see where the level really is. Testing the trans?? At normal temp in park or neutral?

Calbha

okay heres what ive found. first of all my problem as stated in the post is NOT limp mode as is neatv8man the car goes through all four gears it just doesn't hit 4th till 120 mph as its supposed to when its in sports mode.....second testing the wires going to the SEM switch ive found that the grounds are fine but there is a positive going to a motor which switches it into E everytime the car is turned on which isn't getting power....my therory is that if there is a positive going into the three progged switch is going off the same power that goes into the motor of the switch this would cause the car to always think its in sports mode since the switch cant tell it any diffrent.....3rd guess would be after looking at some wiring diagrams it appears there could be a transmission control relay and if this went bad could this be why the switch isn't reciving power (have no idea where or what the tranmission relay could look like)....also the three pronged switch has a yellow wire and a green wire and a brown wire anyone know what the green and yellow are? the brown has to be ground......finally i just had the rear main seal replaced and had someone do it for me for a grand so replacing the transmission is out of the question because (a) i dont have the tools or knowledge myself and (b)the transmission works fine its something electrical......as for shifting hard neatV8man all 1990 3.6 v8s shift hard when the transmission is cold as long as you get a positive shift with no slipping your fine mine does it too......please help because i love this car and am about to sell it to a rich ricer for 5k as is with a 3000 watt sound system to make him distracted from the rest of the car ;P oh and my car the M doesn't come on and the switch wont flip into E like its supposed to when the car is turned into the on position.....i hooked up a 12+ wire to the motor and it flipped like its supposed to im pretty sure this could be a relay problem.

see link below for looking at the wiring diagrams as they confuse me.<ul><li><a href="http://www.eserviceinfo.com/download.php?fileid=13265">http://www.eserviceinfo.com/download.php?fileid=13265</a</li></ul>

Calbha

well after ripping out the entire interior and everything i found theres yellow and blue wire that goes from the switch i found out travels through the center consol and to a little 213 relay thats kinda dangeling right by the fuse panal......changed it and problem solved! guess this goes to show you kids K.I.S.S. (keep it simple stupid!) as for the ones having the limp home mode problem i suggest checking out the multifunction switch thats mounted on the side of the transmission right above the shift linkage, (brownish whiteish color from oil maybe?) youll find that that switch tells the transmission what gear the shifter is in. if the allen screws loosen youll find that the switch can get off alignment and then the car gets confused as to what gear its in. without taking the screws off, (but loosening them) you can rotate the switch slightly and try and put the alignment back in. theres also allen wrench screws on the shift linkage and moving that back or forth might help. youll need someone in the car to shift around the gears while your under there to see what gear is what on the switch and to make sure that you can shift through all the gears,( make sure you can go into park easily i made the mistake of where it felt like it was in park but said reverse in which case you either have to slam it into park or put it in nuetral to start the car).....if you take the switch off, (i took mine off to clean out the inside),((requires removing the transmission mount to get to the screws easily and a rivet gun to put the switch back together)) you can actually change the cars gears without shifting the gear selector.....this is where the other person comes in handy to tell you what gear is what or if it goes into limp, while your playing with the switch,(if it goes into limp mode youll have to put the car in off position then in the on position).....things have to be aligned VERY precisely in order for the gear selector to work properly.....one last thing if you take off the transmission mount to get to the multifunction switch youll have to jack up the transmission to get the bolts back in, (this creats a problem though if you align everything with the tranny mount off as when you put it back on the shift linkage will be in a diffrent position once you put the transmission mount on).
hope this helps a little

paulpas

Part number: 443951253J

paulpas

Position #12 is the guy to replace?

Carolim

Hello! it´s old theme, but did You found what was the problem, beause I have the same issue with my 90 3,6L V8. Morning cold start and car goes off in 3rd gear. After fiew kilometers when it is warm, I turn engine off and on again and all the gears are back and now it works for all day. Next morning same again.