velly s8 uk

hi please can anybody help me
i got audi s8 1998 4.2 v8 32v engine code ahc
it have problem when select manual mode,drives fine in auto mode ,when select man mode and 1st gear and up it change it self and after i dont got control of selecting gear and go into limp mode.
fault cod is p0731 gear 1 ratio incorect.been advice mayby wet trans ecu
tcu or fault in trans box.oil is fine,drove car 20mil in auto mode and drive fine mystery please help thanxxx

silverd2

I don't have the knowledge to help much...others do.

But, for the time being, the trans TCU is under the hood in the electronics box, in the fresh air plenum.

velly s8 uk

hi thanx for your ansver,been at audi they say that is maf sensor cause gearbox fault,they advice to change gearbox and maf sensor at first.cant find gear box any where with my part number 01L300041LX.
must be other a8 or s8 gear boxes to compatible with my gear box.they wont tell wich is others compatible for my car,any idea on this thanx alot my audi is s8 98 4.2 v8 quattro 32v 340bhp engine code ahc thanx again

silverd2

First...go to another dealer or better, an independant German car mechanic.

The MAF can (not common) cause the trans electronically to go into limp mode. Limp mode is an electronoc (TCM) safety measure when a problem is detected...it could be an internal trans issue. BUT, if the MAF fault caused the limp mode, there is nothing wrong with the trans.

Limp mode is decided by the trans computer...NOT the transmission itself.

The MAF can NOT do damage to the trans itself.

Have someone else (or yourself) put a new MAF on the car, reset codes, then drive it. If it go into limp mode again, there's another problem...probably trans internal.

velly s8 uk

hi thanx to your kwik ansver il change maf and go from there il speak with u soon thanx mate

AudiAllroadCO

I know this is an old post which can be a good thing as you likely have found the problem AND the solution by now!! Any chance you can finish this thread once and for all and let us know what problem(s) you found and what your solution was?! Thank you!