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Hi all, annoying fault with my coupe as it goes into limp mode intermittently, mainly if under load.. Things I've done so far is defap and a remap but still no cure despite getting the anti-pollution light and engine management light, I'm guessing that anti-polution could mean anything! if I switch the engine off for a few minutes it resets and all is well for a while, I have just ordered a lexia clone so hopefully won't be stabbing in the dark as regards to diagnosis. Im thinking possible turbo vanes stuck or actuator. Or maybe vacuum control valve, I've also heard that the swirl valve actuator can cause a anti-polution fault despite mine looking like it works.... Another question is can anyone identify what vacuum solenoid does what in relation to the 5 that appears to be on the car! Thinking of swapping them about. Also going to try new vacuum pipes.

I think there are 6 on the car...

One the bulkhead from left to right;
Turbo-Grey plug, EGR-Blue plug, Air doser-Black plug.
On the back of the airbox is a blue plug solenoid - this controls the 2 oily crappy ones on the doser on the inlet ( one flap for cold air in, one flap for warm air in via the exchanger behind the rad )
Also the swirl diaphragm, which is bolted to the RHS of the engine, just below the vacuum pump.

Normally an EML on a 2.2hdi is vacuum related - I replaced all mine with some ebay silicon ones for about £5 - 4mm inner diameter.

Does your swirl valve work when you rev the engine?

Thanks for the reply.. Yeah when revved it seems to work, but I have read they can still be at fault? I can't find a part number for it though.. Any ideas? The car seems to go into limp mode when under load, has even happened at low speed in a high gear...

As GM says, the common problem is overboost caused by a vacuum leak.
The 2.2's VGT turbo needs vacuum to be applied to reduce the boost.
Even a small vacuum leak can prevent the turbo actuator working fast enough to prevent the boost momentarily exceeding the maximum value and causing the fault.

Is your EGR blanked? If so you can swap the turbo and EGR solenoid to see if it's at fault - I think you can just swap vac pipes and connection, should stretch across.