The Air Mass Meter plays a major part in the Transmission system, if the Air mass meter is faulty, the transmission can't sense engine load correctly, get that changed no matter what you decide to do with the transmission.
In my workshop we fit an Air Mass Meter with every transmission we fit/repair on Audi, VW group and Mercedes
When I put the vehicle in "Reverse," the dash is lit and shows the car in Reverse.
When I took the vehicle to the shop today, the mechanic put it on a device which showed Code # XXXXX An Audi Repair Book I have showed this code as "Fuel trim too rich @ idle (Bank 1)." Could this be the cause of the "Reverse" shudder I am experiencing or are the two problems unrelated?
The Problem may or may not be related to the Air Mass Meter fault, however the transmission won't work correctly while that is reading the air flow wrong. now, is the transmission a 5 or 6 speed. its either going to be the ZF 5HP19 or the Audis own CVT known as the 01J
It is an automatic 5-speed trans with tiptronic.
OK, so its a ZF 5 HP19, from your symptoms i would say there is a fault with the reverse drum, generally what happens is, the drum cracks where the circlip sits, and when you select reverse, the valve body applies pressure to the drum to lock the frictions up, then the car moves, but if the the circlip is moving when the pressure is applied, you will get a judder in the early stages, and eventually you will lose reverse altogether.
So realistically speaking, you need to get you transmission overhauled.
i hope i have been of some help to you.
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