S4 B7 Black smoke.

[DanVag]

Hi,

I have a B7 S4 55 plate 134k miles.

I get black smoke coming out of the exhaust when I accelerate. This doesn't happen all the time. It seems to happen if Ive just come off the motorway come to a stop and then pull away.

I can see the tail pipes drivers side look fairly black covered in soot.

Also I can smell Oil when the car is just idling. I'm using castrol 5-40.

Anything obvious I could check to get any ideas of the fault. If any?

 

[RS4B5]

Carbon build up??

 

[DanVag]

I was looking at getting it carbon cleaned but I don't know if thats possible with a V8. Has anyone had it done and noticed any improvements. The car doesn't feel underpowered at all.

 

[RS4B5]

These fsi engines are notoriously known for this the b7 rs4 d3 s8 I'm sure your engine aswell

 

[RS4B5]

4.2 fsi 5.2 fsi Italian tune up

 

[petetheprop]

The S4 isn't fsi (direct injection) like the rs4 v8 and other b7 petrol engines. So it doesn't suffer carbon build up as badly as the others.

As for the black smoke I don't know but my tail pipes are black in a couple of weeks after I clean them on both my S4 and my 3.2v6

 

[RS4B5]

Yh I wasn't too sure on this engine being fsi the r8 is the rs5 b8 rs4 but I've heard the rs4 engines suffer from it also the v10

 

[DanVag]

I think it could be because the previous owner removed the back CAT and didn't installed the lambda sensors.

Over the weekend I got an engine light on the car and it was a catalyst fault. After further digging I found that the sensor we not installed at all.

Making the car run rich thinking that the exhaust hasn't got up to temp and is compensating.

 

[Dimitar Manolov]

Hey DanVag, I also have my driver exhaust pipe more black than the other one and I also do not have back cats.
My comresion is OK, do not have any scratches in the cylinders, the engine is running smooth but when I'm driving on some gear downhill and touch the throttle pedal a blue smoke comes out from the drivers tube only.

Do you have any progress on your case?

 

[Ricky Burrows]

Hey DanVag, I also have my driver exhaust pipe more black than the other one and I also do not have back cats.
My comresion is OK, do not have any scratches in the cylinders, the engine is running smooth but when I'm driving on some gear downhill and touch the throttle pedal a blue smoke comes out from the drivers tube only.

Do you have any progress on your case?

The last post was like a year and half ago don’t get your hopes up on a reply mate lol

 

[Dimitar Manolov]

I know mate but I'm little desperate yet

 

[Ricky Burrows]

I know mate but I'm little desperate yet

Try starting a new thread explaining your issues you might get a better chance of a bit of help