Hi Chaps, as some of you may know from an earlier thread, I've recently fitted a Mongoose exhaust and since then I've had the dreaded smoking turbo at idle syndrome.

Its thought that the change in exhaust back pressure has highlighted failing turbo oil seals on the exhaust side hence the light blue/grey smoke at idle only.

Any how, since then and only since the exhaust change, I get an occasional pop/bang from the exhaust when I blip the throttle at idle. It is very infrequent, but still its a concern.

It doesn't do it at high revs or on the move, only occasionally if I blip the thottle at warm idle.

Could this be a result of turbo failure and the oil passing into the exhaust??

In every other respect my car performs perfectly, no nasty engine noises, etc...

Cheers:)

Edited March 25, 201016 yr by turbocraigy
incorrect wording

From what I have heard, decatting does result in turbo seals giving up as that increases the back pressure a little..Not sure if I believe that as I had my Z decatted about 3 years ago and ain't had a problem..Yet anyway..But I have read on this forum that decatting would make your seals give up..And if only just changing your exhaust system has done this, then maybe your seals were on their last legs and abit of back pressure done them over..

The popping could be unburnt fuel..

 

The experts should put more light into this soon...:)

again going on what what i know, popping would be a cause to have your compression check, also the nature of your smoking doesn't sound like oil seals on the turbos, but don't count it out just yet. many things cause smoking on the car its just narrowing it down to what it could be, have you smelt the smoke does it smell like oil?

 

Also do you get clouds of it when you bring the revs up or just at idle? from what i know when your oil seals are going it drips oil into your turbos, then when they spool up you get more oil and more smoke. are they smoking on both sides and if so, do you have a balance tube installed? from my research about my own smoking tt, both going at the same time is rare, its usually one after the other.

 

I have smoke coming from mine, it does it under load, and at idle, its not big thick clouds of the stuff and its more white than anything else. it also spits loads of water out of both pipes when you plip it. and my smoke smells of nothing but burnt fuel.

 

Can you get a video up of the smoking? might help a little bit more.

 

Things that can cause smoking tail pipes are

 

Condensation

PCV valve blockage

worn turbo seals

The start of head gasket failure, but there are other symptoms to this, mayo looking substance around the oil filler cap*, and sometimes on the dip stick, loss of water from the radiator with no leaks under the car and possibly oil contamination in the radiator fluid, very lumpy idle with loss of compression on 1 or more cylinders, going through engine oil

 

Other things are, valve seals, as oil could leak into the combustion chamber and cause smoking

Bad spark plug not firing an thus causing popping due to unburnt fuel

 

there are a few things that could cause smoking. what we need is a comprehensive list of what causes and what the symptoms are of smoking out the tail of the exhaust.

 

Please note i could be wrong on a few of these. but from what my research has shown, these are what can cause smoking.

 

**sometimes mayo looking substance on the oil filler cap can be from an engine that has sat for sometime with out being started and formed condensation on the inside.

Edited March 25, 201016 yr by vodkashots

There is no loss of water from the system, no mayo formation on the filler cap. Also the car starts perfectly and runs perfectly. The smoke is more from the drivers side tail pipe and there is no balance pipe in the exhaust.

The smoke only occurs at idle and it has to be left idleing for a few minutes before the smoke occurs.

It is defininately oil being burn't and the level on the dipstick confirms this.

Once the smoke starts at warm idle, when you rev the engine you get loads of smoke for a few moments and then it clears. Then it takes a minute or more to return when left at idle again.

The PCV's + hoses were changed around a year ago.

Remember, this smoke and occasional pop at the exhaust on blipping the throttle only started when I changed the exhaust.

I just wondered if the oil in the exhaust could cause the popping.