Engine Conversion A4S 310R Trans Fault

[gtopaul]

Well the engine swap went great as far as the engine but have problems with the transmission going into limp mode upon more spirited acceleration. I get a code 100 Speed monitoring fault;

Speed ratio n-ab:n-mot
not correct for speed
currently selected

The transmission had a fresh rebuild when I bought it although it had been sitting for about a year. Not sure if I have a transmission problem or a transmission control unit problem. It does seem reasonable that the control unit might have a problem going from the former 525i engine to the M3 engine. I believe the TCU gets some sort of information from the ECU. Anyone have any ideas?

http://members.aol.com/gtopaul/private/525m3002.jpg

Thanks.

Paul

[ryan roopnarine]

though many (maybe most) here will disagree with me, i find my 4l30e is quite particular about throwing transmission programs when it doesn't agree with the amount of air moving through the engine or the width of the throttle opening. does it give you a check engine code as well? that might give you an idea ofwhat is occuring.

[gtopaul]

though many (maybe most) here will disagree with me, i find my 4l30e is quite particular about throwing transmission programs when it doesn't agree with the amount of air moving through the engine or the width of the throttle opening. does it give you a check engine code as well? that might give you an idea ofwhat is occuring.

No check engine lights what so ever. I used the original intake and throttle body from the 525. I read through the E34 eletrical manual at work and it seems to indicate that that the shift signal comes from the ECU to the TCU so maybe that's where the conflict is at.

I've got a few emails out to a couple of trans specialists so maybe one of them will have some clue as to what's going on.

Thanks.

Paul

[ryan roopnarine]

No check engine lights what so ever. I used the original intake and throttle body from the 525. I read through the E34 eletrical manual at work and it seems to indicate that that the shift signal comes from the ECU to the TCU so maybe that's where the conflict is at.

I've got a few emails out to a couple of trans specialists so maybe one of them will have some clue as to what's going on.

Thanks.

Paul

aaaahhhhhhh
did you use the same throttle position sensor as the m50 or the m3 one on the throttle from the m50?

[gtopaul]

No check engine lights what so ever. I used the original intake and throttle body from the 525. I read through the E34 eletrical manual at work and it seems to indicate that that the shift signal comes from the ECU to the TCU so maybe that's where the conflict is at.

I've got a few emails out to a couple of trans specialists so maybe one of them will have some clue as to what's going on.

Thanks.

Paul

Then again, the only thing different on the intake side is the use of the later idle control valve from a vanos E34 (same part # as 95 M3 valve) and the mass airflow sensor. The engine idles fine and revs quickly in neutral or park.

Paul

[gtopaul]

aaaahhhhhhh
did you use the same throttle position sensor as the m50 or the m3 one on the throttle from the m50?

I used the M50 throttle position sensor. But, if it was the throttle position sensor causing the problem wouldn't the fault code indicate that? I did run across some Trans Program postings that indicated the throttle position sensor.

Paul

[ryan roopnarine]

I used the M50 throttle position sensor. But, if it was the throttle position sensor causing the problem wouldn't the fault code indicate that? I did run across some Trans Program postings that indicated the throttle position sensor.

Paul

i've gotten "trans programs" for a throttle plate that wouldn't close properly that indicated the TPS, the MAF and the ICV--it also only showed up when i engaged the kickdown or wot'd the throttle (the car didn't know what to make of the TPS reporting) in the m50, those three are closely connected, and if one can't reconcile the data the others are producting, the normal m50 car will throw a trans program. does the 4l30e TCU hook up to the m3 computer through the stock 525i wiring?

[gtopaul]

i've gotten "trans programs" for a throttle plate that wouldn't close properly that indicated the TPS, the MAF and the ICV--it also only showed up when i engaged the kickdown or wot'd the throttle (the car didn't know what to make of the TPS reporting) in the m50, those three are closely connected, and if one can't reconcile the data the others are producting, the normal m50 car will throw a trans program. does the 4l30e TCU hook up to the m3 computer through the stock 525i wiring?

The TCU is behind the passenger side kick panel speaker and is factory wired there so I assume it doesn't have a problem communicating with the M3 ECU through the stock wiring. I still have the old 4L30E I removed from the wagon so I could swap out the speed sensor if need be. I bought some electrical contact cleaner and thought I might as well spray out the electrical connectors on the trans on Monday. It spent about 90 days on my patio so might have developed a little build up on the contacts. The speed sensor is on the tailshaft or inside the valve body area?

Thanks.

Paul

[gtopaul]

Well the engine swap went great as far as the engine but have problems with the transmission going into limp mode upon more spirited acceleration. I get a code 100 Speed monitoring fault;

Speed ratio n-ab:n-mot
not correct for speed
currently selected

The transmission had a fresh rebuild when I bought it although it had been sitting for about a year. Not sure if I have a transmission problem or a transmission control unit problem. It does seem reasonable that the control unit might have a problem going from the former 525i engine to the M3 engine. I believe the TCU gets some sort of information from the ECU. Anyone have any ideas?

Thanks.

Paul

Got some great help from Kirt Koeller a euro transmission specialist in Michigan. He said wrong control unit for the transmission and sent me another to try out. It worked great and the car shifts fine now. No more Trans Program lights or bumping 1st and 2nd shifts. Many thanks to Kirt! The car runs fine and now shifts fine. Total funds expended in the swap about $6k. What the heck, at least I won't see one every 5 miles. ;-)

Paul