W220 S320cdi Exhaust Smoke From Bonnet

[jprgizmo]

Hi, I'm another new person to the club so please be gentle if I have got this wrong.

I only got this last year and am really happy so far, only had to change the brake pads really and all pretty going well. However, recently I have noticed that when I first start my car which has only done 80000mls and especially if I rev her just a little, there is smoke coming from under the bonnet, mainly from the drivers side but just just a little from the passnger side as well. I have tried to look where it is coming from but I'm not sure, maybe where the turbo is bolted on to the exhaust? I have recently replaced the air & oil filter and synthetic oil.

It seems to be running fine, I can her the turbo kick in when I put my foot down, it doesn't appear to be loosing (or lost) any power, never has a problem starting (has been a bit 'bubbly' once or twice). Someone told me there is a big clamp that holds the turbo to the exhaust and it could just but that but if it is, is there seals or gaskets or paste etc. required as well as a nwe clamp?

Hopefully I've given enough info, I would be grateful for any support please.

 

[paul m]

is it exhaust smoke or burnt oil smoke ,if its exhaust smoke there will be evidence of it by way of soot, area to check is exhaust manifold to head, and turbo clamps, remove airfilter housing complete, fairly easy job, this exposes manifold and turbo, check tightness of manifold bolts to head and turbo clamps, esecially rear two bolts on manifold near bulk head,( have known these two to come loose also makes a strange whistling noise) the main thing to remember is if has a leak in this area it will be black and sooty

 

[jprgizmo]

Hi Paul, thank you for replying so quickly. There isn't really a smell if I'm honest, neither burning oil or exhaust, just blue ish in colour. There is a little bit of dark dust, I suppose it could be soot but with it only being thin, I hadn't thought of it as soot, just dust but it certainly could be soot I guess. I've had the air filter box off and cleaned everything, I could only see one big clamp and whilst it wasn't exactly loose, it could be moved slightly. Is there more than one of these to replace if needed and is it a paste or seal job or just clean joints and the clamp? I'll certainly check the manifold to block bolts, didn't think of that. Thanks again, you're help is very much appreciated.

 

[paul m]

as far as i know it will be just a clean clamp up type, try and look for a break down of turbo / exhaust parts prob find it on this site somewhere

 

[jprgizmo]

Also, apart from the thanks......of course I need to let you know what the problem was; it was indeed a broken turbo / cat clamp, one leg had snapped at the bottom which explains the slight movement as well. Its replaced with an upgraded one these days with proper bolts and seems to be fine. Strangely, it starts faster but also sounds smoother and has marginally more power (especially on pick up) even though the gap must only have been small. A few extra mpg would be the final welcome point, I'll wait and see. Thanks again for your help, I am very much obliged.

 

[trapperjohn]

Really pleased its sorted. Your experience and solution will be stored away in the minds of the gurus on here.

Thank you for posting.