Changing tensioner pads in 15 minutes
 

05 A6 C6 4.2 with 160k. Timing chain service done at 150k. Although I have not verified, proof Mark on chain's indicate genuine Audi and although the cams look great wIth very little scorching, it is evident that the chains are new.
I had the dreaded broken pad on the drivers side rear upper tensioner. After removing both valve covers it looked as if that pad had not been replaced with new when service was performed (dark brown compared to other visible pads being tan with no wear) I jumperd intervaled 12v to the tensioner and created enough slack to swap out broken pad without removing cam or cam bolts. Several rotations and the chain was tight as could be.
I can see what I believe is the timing Mark on one of the teeth of the cam sprocket when it is just south of the tensioner. What I cannot see is its point of origin for verifying timing. Can anyone tell me if you can verify timing without removing the engine? I fear that the broken tensioner pad caused the vehicle to skip timing a tooth or half a tooth. Vehicle was sluggish off the line but smooth after a short while or higher rpm. Any insight will be greatly appreciated! https://cimg5.ibsrv.net/gimg/www.aud...e7689ab8a3.jpg
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