S4 exhaust question

[s4mark]

Hi all, well had the s4 for a few months now and still so pleased however I have noticed that the left exhaust pipe gets very black and sooty quickly where as the right hand one seems to stay pretty clean. Anyone have any idea why this might be happening? Does one do more work than the other or may it indicate that a sensor has gone bad causing it? I plan to get it down to the specialist I use when i get a chance and no doubt they will stick it on vag com but just thought I would see if any one else has had this issue.

Other than a slightly noisy fuel pump, I cant really fault it, car seems to run fine and check oil level religiously every week. Any ideas appreciated.

Thanks

 

[colinurquhart]

The two exhausts are completely independent but my left one soots up quicker than the right also but it's never really bothered me too much. It will be interesting to hear what your specialist says so I'll keep an eye on this thread.

 

[dualmono21]

tiptronic or manual ?
the tiptronic exhaust has valves in it which open at a certain rpm if one of the valves is stuck then this could be the problem

 

[Paul @ Unit 9 Remaps]

Maybe an Injector' Possibly EGR could be a few things maybe sooted up CAT theres a few possibilitys it could be

 

[colinurquhart]

tiptronic or manual ?
the tiptronic exhaust has valves in it which open at a certain rpm if one of the valves is stuck then this could be the problem

They all have the exhaust valve on the back box.

 

[s4mark]

tiptronic or manual ?
the tiptronic exhaust has valves in it which open at a certain rpm if one of the valves is stuck then this could be the problem

its a manual

 

[colinurquhart]

Also I doubt the valves would be the issue as I've just changed my exhaust and now have no valves and still my right pipe soots up quicker.

 

[dualmono21]

not seen a manual mate
so didnt want to assume they were the same or indeed differant
ive also changed my exhaust but both exhausts seem to soot up around the same

 

[GeoffDunk]

I recently had my valves serviced and checked for operation as one side sounded louder at idle than the other and sure enough there was one stuck open, both now operating correctly and still the left hand tail pipe soots up a lot more than the right.

Mine is also a manual and I had never really thought anything of it but would be intrigued to find out why this happens, seems common though.

 

[deano1978]

Same with mine too. I put down to the way the pipes divide. If you have a Y shape splitter then it should split evenly. But mine is a straight through then branches off to the right.

If you think of it like a long straight water slide,but then add a slide on the side,majority of water will still flow down the main slide,but some will flow down the side too. Just not as much.

Thats my theory anyway

 

[GeoffDunk]

Same with mine too. I put down to the way the pipes divide. If you have a Y shape splitter then it should split evenly. But mine is a straight through then branches off to the right.

If you think of it like a long straight water slide,but then add a slide on the side,majority of water will still flow down the main slide,but some will flow down the side too. Just not as much.

Thats my theory anyway

The S4's V8 exhaust doesn't split or intersect for that matter, individual pipes front to back, no Y-splitter.

 

[s4mark]

The S4's V8 exhaust doesn't split or intersect for that matter, individual pipes front to back, no Y-splitter.

at least it seems a common issue so that makes me happier. Once its been down for its health check i will post to let you all know what they say

 

[deano1978]

The S4's V8 exhaust doesn't split or intersect for that matter, individual pipes front to back, no Y-splitter.

:O

 

[Paul @ Unit 9 Remaps]

Same for the 3.0 V6 also