Hi, I have a 2008 Mazda 6 2ltr Diesel
I recently had to replace the Air flow sensor as my car was running rough and although this fault did't show a light on the dash, it did on a computer that was plugged into the car.
The original problem was that the car ran rough, no power, and would sometimes throw out white smoke, which would indicate unburnt fuel.
After replacing the faulty part I had no change with the general running of the car, so took it to Mazda for them to plug in.
No fault found, and the car behaved itself all the time that they had it.
They did advise that it could be a sticky turbo boost valve and to try running Wynns turbo cleaner through the fuel system.
Well it behaved for bout two weeks with to minor hiccups.
but today the problem came back with avengance, max speed 20mph white smoke, and no power whatsover.
So I called the mechanic who usually works on my car, who took it for a road test. THE CAR DIDN'T MISS A BEAT!!!!
Firstly, anyone got any ideas what's wrong, or do I need a Priest to give it an an exorcism?
Any help greatly appreciated

 

Not a mechanic and never owned a diesel so I can't help. I can sympathize. It seems that most of my issues are followed by the dreaded: "Unable to duplicate customer complaint".