Loss Of Power A4

[98 A4]

Originally Posted by Donald M

Hi there,

I am now a member of this club too. I have a 1997 with AFN engine and 134K on on the clock. The exact same problems as above and I have replaced the MAF but to no avail.

Have just spent an hour looking at it in a howling gale here in Inverness and noticed that there is a plastic spherical thing rattling around under the turbo. It has a pipe going to it and seems to be involved in the turbo process. Does anyone know what it is?

Also, can anyone tell me I can locate the ECU and the hoses that go to it?

Regards, Donald

The plastic piece that you are talking about is probably the BV(bypass valve) there should be a vac hose that goes from the BV into the intake manifold.

[bigcrags]

This morning I unplugged and sealed the vaccuum hose on the EGR valve and suddenly no more black smoke and crucially the car isn't going into limp mode. Full service resumed, it would appear.

Does this mean that I had a sticky EGR - sticking open when the car was under load? Or could it still be the N75 that was causing it?

And will I damage the engine if I just drive it as it is without the EGR connected?
Thanks