Chet Owens

My RS6 had 178,000 miles on it when the wiring harness that runs between the engine and the firewall caused the ECU to fail and cratered cylinder 2 and 7 due to pre-denotation. The problem was discovered after installing a new short block. The Audi dealership mechanic spotted the harness having damage like some of the other Audi's and VW's. He cut it open and the two of the main leads had shorted together due to the sheathing cracking and falling off. The new harness has two of the main wires with newer sheathing technology. I highly recommend RS6 owners checking their harness for heat damage. $1600 part can save you about $24k in a rebuilt engine

s4master1

how come it was not discovered before it created any major damage?
is very easy to spot when there,s detonation, and usually the valves are the first ones to get holes on them.
tell them to check if the mixture is too lean.
is your car chipped?

Chet Owens

Engine was running perfect until the harness shorted the ECU out. No damage to the heads. The only way you would know to look would be someone telling you. BTW the day it failed the car was going about 40 mph down the road. cylinder 2 and 7 did not misfire they fired halfway during stroke due to the ECU telling it to