Mk 1 Tdi Auto - Juddering And Black Smoke ?

[Guest italiastar33]

My neighbour' s Alhambra auto w-reg has started juddering whilst acelerating, puffing out black smoke and he can hear a scraping noise coming from the engine. He changed the MAF sensor after advice from here about 15 months ago. Any ideas, please?

 

By the way the main dealer who serviced it could't find anything wrong with the car - they said "computer said no" ie they checked for errors and therewern't any so there wasn't anything wrong - the car puffed it's way out of the dealership, complete with a new MOT and juddered home. This is the same dealership who told me that I didn't have to worry about the possibility of rusting following a sill repair as the Alhambra was fully galvanised !

[TimsBamma]

I think that black smoke normally indicates over fuelling, any smell of petrol/diesel?

[Guest italiastar33]

I think that black smoke normally indicates over fuelling, any smell of petrol/diesel?

 

Ii's a diesel - I'm not sure about smell as I'm going by my neighbours description - however that sounds feasible as a fuel problem could cause the juddering.

[big_kev]

This sounds bad to e.

 

Loss of compression possibly ...not good if it is

[seatkid]

First check the air filter is not blocked. Then get the injectors checked/cleaned at somewhere like a Lucas diesel service centre.

[italiastar]

First check the air filter is not blocked. Then get the injectors checked/cleaned at somewhere like a Lucas diesel service centre.

 

Thanks SeatKid (How are you - long time no speak). He brought it to an independant who fixed the black smoke by changing the fuel filter (something the main dealer hadn't changed in 6 years !!!) and putting in some injector cleaner. He's still got a problem with lack of power though - MAF changed thanks to your advice last year. He's also getting a noise sometimes when running - diifucult to describe, but sounds like something spinning and rubbing - indep garage first thought a turbo problem, but now suspect auto gearbox. Somethimes he cant get the car above 40mph flat out?

 

Any ideas?

[Richard gal]

Is there a reason it wont be the maf sensor again?

[italiastar]

Is there a reason it wont be the maf sensor again?

 

Mmmm - possibly (must admit it did cross my mind as I typed it) - that wouldn't explain the noise, but that could just be a red herring. Thanks.

[littledaz]

Could be MAF sensor but, have all the induction pipes from air filter to turbo to inlet manifold been checked.

 

If you have a small split in any of the induction pipes you will experience,

 

1. black smoke (I know you say this is fixed but may improve further)

2. lack of performance

3. induction noise, which sounds like scraping under load

4. juddering due to the unmetered air which is not passing through the maf sensor.

 

Does all that sound familiar? ;)

 

It is worth a check because the split may not be noticeable at idle due to there being no boost from the turbo which is why it is probably difficult to diagnose. Try revving the engine hard and listening for escaping boost air with the bonnet open.

Doesn't always throw up fault codes either. I take it the engine is a 110bhp tdi? They have small rubber connecting pipes that join the hard plastic pipes to the turbo and inlet manifold. The oil mist in the induction system usually makes them go soft over the years and they usually split where the jubilee clips are but, still worth checking all the pipes.

 

Hope this helps ;)

Edited January 24, 2007 by littledaz