Smokey Passat

viv2

Hi i have a 01 tdi passat which blows black smoke in the low gears and after third its grand. had it serviced recently and mechanic said intercooler was damaged would replacing this solve the dark smoke?

L-M

Is it remapped?

Ferris

Generally black smoke == incorrect fuel mixture. This could be cause by a charge air leak (intercooler) as the engine will mix enough fuel for a given quantity of air but as the air is escaping to atmosphere the engine runs rich.

Blue smoke however == engine oil and this is usually the sign of a blown turbo in the 1.9tdi.

I'd get a new intercooler, GSF have them afaik, or a scrappie.

viv2

Thanks not remapped mechanic says intercooler looks like it had a bang from a rock but still has plenty of power in turbo. Any chance i can replace it myself if i get the intercooler or is it a big job.

Ferris

viv2 wrote: »

Thanks not remapped mechanic says intercooler looks like it had a bang from a rock but still has plenty of power in turbo. Any chance i can replace it myself if i get the intercooler or is it a big job.

Its a common fault as the intercooler is quite low. Its on the drivers side in behind the bumper (on a golf but I think the passat is similar) so that has to come off. Its pretty easy to take off on the golf. Just bolts in the wheelarches and under the grill(has to come off too) and remember the temp sensor connector when you are removing the bumper. Then the intercooler should be easy to get to, you'll need some spring clip compressors to take off the boost hoses however. Replace these with spring clips. Try emptying the intercooler, if there is oil in it then your turbo is donald ducked.

viv2

just checked intercooler traces of oil can be seen so wondering will fitting new intercooler clear up the smoking

viv2

anyone

Slidey

If intercooler is knackered you should hear the boost air leaking.

It could be the mass air meter, these give a lot of trouble on VW, leave you down on power, not 100% sure about causing smoke though

viv2

yeah im getting a noise like its losing air all right have an intercooler in the post just hoping this does the job

Slidey

Join the 2 pipes together for the time being if you can

That will check the pipes for leaks and keep you going without the smoke if it is just the intercooler

viv2

no real loss of power in the turbo and do i just remove the intercooler and connect the pipes will this do any damage

Slidey

viv2 wrote: »

no real loss of power in the turbo and do i just remove the intercooler and connect the pipes will this do any damage

It shouldn't do.

In this cold weather you prob wont even notice the difference!

Dont kink them when joining them up, you will prob need a bit of pipe for this, not sure of the set up on a passat so I cant be more specific

viv2

im thinking the oil in the intercooler is causing the black smoke if replaced it might stop

Slidey

Some oil can be expected to be lost as turbos get older, its no big issue to find a trace on the inside of intercooler pipes but if it is gathering in an intercooler its a sign that the turbo is on the way out

Ferris

viv2 wrote: »

im thinking the oil in the intercooler is causing the black smoke if replaced it might stop

Not generally the oil is more likely to stay where it is, there is a big rise to the injection manifold and I don't think that the oil would make it into the engine in big amounts. When you take off the intercooler pipe, turn on the engine, if oil drips from the pipe with any regularity then your turbo is knackered. Thats how i confirmed it on the golf I had (for the 2nd time:mad:). Oil consumption like that would be noticible wrt top ups etc.

Also burnt oil gives bluey smoke and in every gear.

If your intercooler is gone than start there, if the problem persists then it may be mass air meter. Both are common problems on VAG diesels.

Mr.Diagnostic

An intercooler can be damaged without leaking. In general there will always be some oil in the cooler so it will leak out where boost leaks out. If the damage is dry the boost leak may well be elsewhere. The common place for these to leak is on the high pressure pipe from the turbo. The split is usually very small and difficult to see with the pipe in place. Remove it to check.

ShayK1

how much was the new intercooler if you don't mind me asking?

Matt Simis

If the intercooler (or IC tubuing) has a hole in it then the Turbo is being overworked trying to make up the lost pressure (that is venting to atmosphere through the hole). Thats a sure way to wreck the turbo.

Slidey

[pedantic]There will actually be less pressure on the turbo when the intercooler is leaking,

When it is open to atmosphere boost pressure will be down, which means the turbo will be spinning free[/pedantic]

viv2

bought online for £90 posted can give you details if you want. Car was looked over quickly today no loss of power so far on the turbo definitely losing air when car is reved will replace intercooler the weekend and see how it goes but he thinks that will solve the black smoke problem

viv2

any help on removing the bumper would be great help to me.

Ferris

viv2 wrote: »

any help on removing the bumper would be great help to me.

On a golf (should be similar to the passat):-

-Jack up car onto axle stands and remove the front wheels.
-Open bonnet (do not close till finished)
-Remove bonnet release handle (plastic bit) this is a bit fiddly, I used a small screwdriver to prise the plastic forks off the stud on the release catch.
-Remove grill, should be held on with screws.
-This will reveal torx screws holding the bumper on, unscrew these.
-Pull out the black plastic vents at each side of the bumper and undo the torx screws behind.
-there are yet more torx screws holding the plastic wheelarch liner to the front bumper, undo these, they will be a bit mucky so a quick scrub or powerwash beforehand will help here.
The bumper is now only held on by two sliders underneath the indicators and the temp sensor wire.
-Pull the bumper forwards at each side and it will pop off. Do not pull too hard as you have to undo the sensor connector. Its useful to have a spare hand here to avoid dropping the bumper on the ground and scratching the paint.

Hope that this helps.

ShayK1

There is also a plastic cover underneath, its ike a dirt protector for the engine.
It is held on by a flat headed screw in the middle and a few torx either side.