1.5dci 106bhp laaaaaaaaaaaaaaaaaaaaaaaaag.

[Boggy22]

Hi guys, came back with another problem.

I noticed for a few months that I have a 1-2s lag when flooring the gas pedal in any gear and from any rev. Sure, below 1800rpm I'm not expecting much response, but when I'm at 2000rpm and floor it, it starts to pull only about after 1.5-2s. It's not completely dead, but it starts pulling veeery weakly, coming strongly only after that long pause.

At first I thought it's the MAF, as with the MAF disconnected, the engine is very very responsive. Sure, less power on the top end and an average amount of smoke, but that's to be expected if it doesn't know how much air comes in. I ordered a new (Continental VDO) MAF and replaced it, hoping the car will go back to its former glory performance, but the lag came back again.

Since then I have replaced the MAP as well with a new Bosch one (my mechanic said I should as on idle it was showing 998mbar, when it should have been around 1020-1030) and now it's showing correct pressure. I replaced the turbo boost converter (boost control valve) with a new Pierburg unit.

The problem is still there. The CLIP test showed only one error, DF641 - Inlet air flap circuit. The EGR should be working ok, car doesn't smoke, and my mechanic said if there's only the littlest problem with it, it will give an error code. I also drive quite sporty and fuel with good diesel, so the engine should be on the clean side.

Do you think there's a problem with the Air Flap, can it "semi-close" while the engine is running? I thought it only has two positions, "Closed" with the ignition off (to starve the engine of air), and fully open with the ignition on.

Turbo spools up quickly to 1.54bar, I can see the graph in Torque on my phone(the car is re-mapped to 125bhp/320nm), so I don't think there's a problem here either.

Thanks in advance for any input!
Bogdan