406 Hdi poor running with MAF connected

[gammaphile]

Hi, Dunno if anyone can help but here is the problem that is driving me MAD.

Car run's real bad with the MAF connected.
Problem started with what i can only describe as a misfire, engine would stutter and loose power or i could sit there with my foot on the floor but it would not accelerate. I would get no boost or the engine would accelerate as normal and then stutter with bursts of normal acceleration.
I traced the problem or so i thought was a duff air flow meter. With the meter disconnected then engine would drive better IE: no stutter but with a loss of low end power.

I have replaced the Air Flow Meter but everytime i connect up the new meter i get the same problem back.

The car has been serviced with new filters and a a diesel cleaner has been flushed through the fuel system.

Any Ideas ????

Cheers Paul

[steve_earwig]

Hi there. Not much help but what if disconnecting the MAF is putting the car into "limp home mode" and is masking the real fault that the system can't detect? When you connect the MAF again it comes off LHM and shows up the fault. LHM should bring up the engine management light though.

[gammaphile]

You see that's where it's strange, with the maf disconnected there are no warning lights coming on and the engine appears to be on full power apart from the bottom end being a tad fluffy. Its bloody annoying and typical seeing as i am driving to the south of france on Friday

[Welly]

There was a problem with the wiring loom on some models and the trottle pot and MAF share the same earth! dealers used to splice in separate earth to sort this out. Maybe you have this problem?

Have a look on here http://www.ilexa.co.uk/forum/index.php? ... board=22.0 but you'll have to troll through all the 406 stuff i'm affaid.