Blixt

I have a problem that I cant find any answer to, search the net for hours...
I got myself a 2004 RS mk1 with 144000km on the odometer.
3" Mongoose, IC Pro alloy, special map since 2004, K&N air filter.


Whit cat on I get smoke when I floor it and change gear, when I de-cat it I get a puff every time I change gear, if I floor it I get a huge cloud.
The former owner did an overhaul on the turbo, made no difference at all.
There is no smoke at start-up, could not be valve seals then?
It has a really bad idle when I have the cat on, stops 1 of 3 times when I hit the clutch for a junction.
If I change gear and support with gas, don't let the revs fall down, then no smoke...
It don't seems to use oil or water, new spark plugs fitted (Denso), cleaned the air filter.
There is a little dent on the oil return from the turbo.
Checked the vacuum pipes for leakage or bends.
The smoke looks blue in the mirror but I'm not sure because of black tinted windows (its not white smoke).
Black soot in the end pipe.
It run like a rabbit on speed, so cant say there is any other fault on the engine.


Anyone with ideas about what to do next?

Sorry for my bad English.

H3lsing

The blue smoke is usually associated with turbo problems, oil being burned etc.

bigdel

My lad's FRS did the same. when we took it to bits you could wiggle the turbo compressor shaft about 2mm either way. Turbo needed a complete overhaul

jc2000e

i had similar issues on my old delta integrale years back turbo was screwed.

Blixt

Thanks for the answers.
But if its not the turbo (the former owner had it totally overhauled) what to check next?

H3lsing

I wouldn't rule it out, overhauled or not.

rooos

sorry, i'm not such familiar with turbo issues,

but for n/a i'd say: blue smoke...
-... when start up, after a throttle release+floor it => valve seal or guides,(or thin valve/s),
-...after idling+floor it => piston rings.

you may also have some issues with the crankcase ventilation...
this might be detected running it, in normal condition, with the crankcase ventilation hoses disconnected for a while (not too much, to not to soil the engine bay with oil vapours).

but it could be either a badly overhauled turbo. even good technicians do mistakes...

i apologize for my bad english too.
hope it helps you to find out what it is...
(i'm curious too) keep us posted on this one.

Blixt

Could these marks on oil return pipe make my car to smoke when changing gear?

jonfoc

Those dents won't make a difference. I had a brand new turbo that smoked badly on over run. It's easy to take the turbo off so check it rather than rely on what someone says. Next I would check stem seals

Blixt

Problem solved after changing dump valve, no smoke on shifting gear and perfect idle.

big_wasa

The oem ecu does not like dump valves. It's a maf bassed system. The ecu will be dumping in fuel for air that was vented to atmosphere instead of being recirculated.

Blixt

What!!!
The car need a dump valve, blow of or what you like to name it otherwise you will kill the turbo.
And it should always on FRS be a recirculated otherwise you will run in to trouble, so that was already checked long time ago before I ran in to this problem.
My answer to my thred was if someone ran in to a simmilar problem this might be a solution.

big_wasa

To add to my post, the Oem ecu does not like atmospheric dump valves for the reasons I've put.

Yes the Rs has recirculating bov/ dump valve call it what you like. Technily you don't "need" one.

So what sort did you change ? Faulty Oem or faulty aftermarket ?