2005 Astra H 2.0 Turbo - Diagnosing limp mode

[Wage90]

Got some shuddering past 3k revs and car shunted into limp mode.

Suspected air leak/something to do with the boost pipes, check the fault code and it's throwing up fault with mass air flow sensor.

So I take it out and clean it, nothing seems to be wrong with it, reinstall it, clear fault code and everything working fine, but suddenly after a week back into limp mode with the same fault code?

Going to check for air leaks, anyone else aware of any other potential causes? Car has very little power at the moment.

Also:

Intermittent start, either fails to start or starts up but then chokes and revs drop until I hit the accelerator then starts to idle fine. (which is why I think there must be a leak somewhere).

ABS light flashes on and off when accelerating around corners.

Cars an 05 plate done 80500 miles.

[sunbeam alpine]

Try swapping the MAF, or try just disconnecting the MAF.

With the MAF disconnected the car should drop into a "safe" mode. If it drives better the MAF's screwed.

[stevieturbo]

Cleaning the MAF isnt going to anything if there is a fault with it.


And wheel bearings contain the ABS sensors...and can give trouble.

[sunbeam alpine]

MAF needs replacing

[Wage90]

Okay so I disconnected the MAF sensor.

It cures the sluggishness, when its connected the turbo does boost but only very slightly, very juddery when first start up, sometimes put the pedal down nothing happens. With it disconnected the turbo doesn't work but it's much smoother.