Smoke at engine start

[Buje]

Hi,

My My07 Sti which i picked up 4 days ago has Full Subaru service history still under warranty until October.

When starting the car i have noticed some smoke from the exhaust it disappears in a few seconds.

So far i think it only happens when the engine is warm.

There is no smoke noticable when driving.

I am not a car expert but any advice would be great.

Thanks,

Buje

[Arith]

What colour is the smoke? Usually smoke means an oil or water leak somewhere. If you turn off the car and start it again, does smoke still come out? Or does it only appear after the car's been off for a few hours and allowed to cool down? When this happened to me 2 years ago, I had to replace my turbo, so hopefully your issue is something else! Good luck!

[tangcla]

I've been told if the car's cold, it's normal for a short puff just as you start it. Especially evident when it was parked on a slope.

[Spec B Wgn]

sounds like oil blow by.

[senator]

How many K's has your car done?

It may have been serviced prior to you picking it up, check your log book, Subaru may have carried out an upper engine clean treatment for you ……This treatment helps clear the intake of any carbon build up…….. This generates smoke for a few days as the rest of the solvent gets burnt off.

Another reason for the smoke could be "blow by", which is oil getting into the intake (no big issue), due to way engine is plumbed it’s a common issue for Subaru's that have been driven hard……. Don't worry smoke will clear after a few days, a catch can does help solve this problem.

Just keep an eye on your coolant and oil levels……………… just too be safe.

[teejay]

had similar problem just after a Subaru dealer service, took it back and was told it was due to oil overfilled by a litre.

[sundayDriver]

had similar problem just after a Subaru dealer service, took it back and was told it was due to oil overfilled by a litre.

so is it supposed to go away by itself after it's drained and the correct level has been filled?

[teejay]

had similar problem just after a Subaru dealer service, took it back and was told it was due to oil overfilled by a litre.

so is it supposed to go away by itself after it's drained and the correct level has been filled?

Logic would indicate that it should self level, Subaru just took a litre of oil out of mine, risk in leaving it and waiting is 'what if it is something else causing the smoke'.

[sundayDriver]

sounds about right. depends on how long the oil was in there for.

if it's just on startup, then a possible cause is the gasket between the "headers" and the throttle body (? where the TGV are) might be leaking. or the pumps used at startup. or the turbo leaking oil onto the cat.

maybe you should get a compression test done.

[TorpedoCreative]

had the same experience after a service... the smoke went after a few days/1 week. Only appeared when I first start the car in the morning/after work - It turns out it was engine cleaner (only wished Subaru had told me to expect it as it scared the sh@t out of me when I saw smoke for the first time!). Havent had a problem since (and that was 6month + ago)

James

[marki]

had similar problem just after a Subaru dealer service, took it back and was told it was due to oil overfilled by a litre.

Too much oil causes high pressure, blowing out engine seals and gaskets, all which if need to be replaced, can be very costly.

[teejay]

had similar problem just after a Subaru dealer service, took it back and was told it was due to oil overfilled by a litre.

Too much oil causes high pressure, blowing out engine seals and gaskets, all which if need to be replaced, can be very costly.

just as well I'm only keeping the car another month, does help others though.