felixjr

Hi all,



I purchased my high mileage (170k) Audi a5 a few months back and have been trying to figure out the cause of my ‘jerky’ transmission. When moving from a standstill the car stutters/jerks forward and sometimes makes a knocking sound when putting your foot down on the accelerator. Works fine when you allow the car to start moving then accelerate gradually. 1st step was getting a gearbox service, didn’t fix the problem but once it gets going can’t fault it at all, drives very smooth. The dual mass was changed shortly after as the noise coming from under the bonnet was horrible, still didn’t fix the problem but car is now much quieter. I thought it may be an air or fuel related issue, I cleaned out the maf sensor and throttle body, although it didn’t fix the issue, the car feels much better and feels as if some power has been restored. I haven’t looked into any fuel related issues yet as all mechanics have told me they believe it’s a gearbox issue but I don’t think they’ve really given it a chance. I’ve taken it to a ‘diesel specialist’ and without looking at it he put it down to a gearbox issue. I then drained all the transmission fluid and added in some ‘CVT magic’ called EX120 to the transmission fluid - it’s essentially a shudder fix. Was told it was really good stuff but unfortunately still didn’t fix the issue. After searching the net endlessly I finally came across a forum that had similar symptoms and said it may be the engine mounts. I lifted the bonnet, put the car into drive without my foot on the brake and finally I could see and hear the noise of been complaining about from the beginning. The stutter and knocking sound was actually the engine moving violently under the bonnet (video attached). So as you can imagine I bought new engine mounts and had them fitted. After they were fitted I did the test again and although there was still some movement it was nothing compared to how it was before. I’ve been driving it like this for 2 weeks now and must’ve say the jerkyness is soo much better however not completely gone. Sometimes I can put my foot down with no jerk but sometimes (when going uphill) the jerk/knock seems to appear again. Again I was advised by mechanics that they still think it’s a gearbox issue but I can’t help but think maybe the transmission mount needs changing too. Again searching online I came across a transmission mount insert which is used to remove the dead space in the mount and stiffen things up. After installing today I’m getting much more movement under the bonnet again and the jerkyness is back most times when accelerating (second video attached). Is it fair to say that the transmission mount probably needs changing too and the reason why the jerkyness is now back is because the transmission mount insert isn’t giving enough free space for the transmission to move around exposing the bad mounts?



Hope this makes sense, any other suggestions would be highly appreciated! Thank you