s320 cdi, excessive black smoke, lack of power and brakes

[aka$h]

Ive had the car just over 2 years and have covered 40k mles in it during that period, its now on 80k.
The car been maintained regardless of cost, having recently had several of the front suspension parts replaced at a cost of £2k.

The car had developed several faults, so i dropped it off to george last week. Faults were:
Itermittant lack of power, very occasional.
Exessive black smoke on acceleraton.
The brakes seemed to be losing vacum.
A gearbox clunk on change from 2-3.

Got my car back from george fraser today, its been there for about a week, and they have changed various parts, but have not found the cause of the problem.

They went through the process of changing several parts,
To cure the brake problem, they replaced the brake servo twice and the master cyclinder, but this did nothing, in the end this turned out to be the vacum storage unit, and they carried out a MB modification. This seems to have resolved the problem, and the gearbox is now operating normally.

The problems still remaining are, the power loss and excessive smoke, they suspected the intercooler and replaced it but this seems to have had no effect.

It wil be going back to george next week, I know he will find the fault in the end, just wanted to see if anyone has had similar problems, so I can suggest a few things.

Thanks

 

[aka$h]

Thanks for the info, ill get him to check that out.
And it also seems the brakes are still not back to normal, its fine on motorway style driving, but around town when in slow moving traffic the brake pedel goes all the way down.

 

[aka$h]

Its difficult to comment on the braking problem without seeing the car myself but it definately sounds like you have some sort of a vacuum problem possibly with the servo leaking internally. its hard to tell with this problem without seeing the car.[/I]

Its got to be a vacuum related issue, but they have tried 2 new servo units and a master cyclinder, guess ill have to drop it off again and see what happens.

 

[se97mlm]

I would have suggested a defective EGR valve that sticks open, lots of clack smoke and less power.