Smoking on startup

[newsh]

My RS4 smokes a bit when I start it, when I left it sitting for a couple of weeks it filled the road with smoke when I drove off. Once warmed up it seems ok although I think I smell a bit of burning oil sometimes when parking and reversing into a space. It has about 80k miles, PRJ live remap, original turbos, 3" DPs and full 3" Milltek, no cats.
Oh yes, the small PCV valve is deleted but the low pressure side is still connected to the Y pipe. It uses a bit of oil but it's certainly not dropping in level at an alarming rate.

What does the team reckon? Could it be stem seals or are we looking at turbos.

[quattro-nick]

what color has the smoke?
blue means oil consumption (valves-pistons-turbo's) and white smoke means water consumption (head-cylinder head gasket-turbo)

[newsh]

Good question, I'm not too good with colours but it smells like oil.. I'll get someone to watch me drive away and tell me.

[martinws]

The longer it sits the more smoke will appear?

Worth a wee look down the bores after leaving it a day or so to see if oil build up on any pistons although if valve shut it won't drop right down I guess.

[DJones]

Hard one to diagnose without some fiddling....

Stem oil seals are normally only a puff on start up and that's it as the valves move to fast after that for the oil to get down unless really bad but they would have shown themselves before now. Rings normally show themselves on overrun I.e. Shut throttle and the cylinders get no air from the inlet valves and have the potential to suck it up the bores.

The turbos normally show themselves on tick over. If I had to decide from the symptoms you have described I would sadly say turbos or at least one of them.

It sounds like oil is slowly entering the exhaust housing when the engine is off and as the engine and turbo housing warms up it burns off which is why it lingers and in perticular shows itself as you drive off as the housings would increase in temperature rapidly. As you know it doesn't take much oil to produce a lot of smoke.

All speculation as its impossible to fully say.

Hope it helps in some way mate....

Darren.

[newsh]

The longer it sits the more smoke will appear?

Yes.

I have to take the IM off to re-seal the IAT sensor soon (small boost leak) so can look at the valve stems then, just need to order the gaskets. I'll make sure I leave it standing for a couple of days before starting work.

[newsh]

Hope it helps in some way mate....

Darren.

Cheers mate. The DPs were fitted at QC only a couple of months back, they had a look at the hot side of the turbos then and nothing seemed amiss. I really does seem like turbo seals to me though..

Must say it goes like stink though and I'm driving at half to 2/3 throttle most of the time

[newsh]

I got my lad to watch the tail pipe as I started it, no smoke then a small puff of blue then just white steam/condensation.. I reckon the turbo seals are on the way but not too bad, drove a few miles, parked up and idling, no smoke visible.


I'll top up water and oil and note the mileage (which I always forget to do) and see how it goes.

[Laaf]

I had a S4 B5 until last May. It smoked alot on the colder months in the year. The exhaust builds up a lot of condensation.

[popdemonic]

if your turbo seals are going bad,normally you will need to wait until the turbo heated up and it'll started smoking out.
Valve stem seals,usually happens on the exhaust valves since it's hundred times being toasted under the high temp.
once you start up the engine,it'll be smoking out promptly since some of the oil will get into the chamber depending on
which exhaust valves stay opening and let the oil deposited on the top of the pistons.

Usually,the valve stem seals will use more oil than the bad turbo seals.Turbo seals is acting like a dynamic seals,the faster
the turbo spin,the better the rings sealed the oil.

if the car smoking out on tick over and rev up the engine with one puff bluish smoke out and disappeared,i would guess your turbo seals are bad and once you rev up the engine if your stem seals gone bad,the more you rev up the engine,the more smoke coming out.

BTDT on bad turbo seals,valve stem seals,worn guides.As i stated,valve stem seals use much more oil than and bad turbo seals.

[newsh]

Good info, thanks.