Hello

I had my brothers Audi A6 1.8T in for a MOT on Monday and it failed on emissions after 2 fast idles and was told I would need to replace the cat.

When my father was driving the car back home he said it was very lumpy and then the engine died and would not start again.

Got the car home and noticed that one of the coils had melted and blew a fuse. What could cause a coil to melt? Could faulty coils cause high emissions? Would the cat be to blame when they tried two fast idles to try and clear it for lower readings?

I know the coils had failed before so I guess a bad cat could be the cause?

I have ordered new coils, a new cat and noticed today whilst checking to see how I will remove the cat (looks like a pig of a job to be honest) that a metal pipe had no hose attached to it near the rear end.

Part number for connector pipe is 06B133607B

I have no idea what is supposed to be attached and where it is supposed to connect to on the rear end. It looks like on front the pipe leads down past the turbo and to the secondary air pump but not 100% sure on this.

I have tried looking for information on this but no luck and would like to get it sorted asap to avoid possible future problems.

I have included some pictures of the pipe below to make it easier for you guys to see what I am talking about







Any help would be great.

Thanks