Ok, so my Mk1 vRS engine management light has been coming on now for for a few months. I have VAG com so I've been checking the fault codes and resetting them each time.

Every time it comes up with the ever popular 17705 - Pressure drop between turbo and throttle body (check D.V) P1297 - 35-00.

 

Only once has this caused any noticeable difference in the cars performance, I've been doing long runs with the light on and it really does still pull like a train!

 

I have cleaned the throttle body, I've changed the N75 valve and checked all the pipes for splits, but the light has just come back on again!

Again there is no difference in performance or MPG or anything......Please help!

I don't want to just start changing bits and it still keeps coming on but is it worth just changing the DV? I've read on here that the factory fitted ones usually don't need replacing?

 

@Tomlin8 - Have you tried draining the intercooler?

No, could a dirty intercooler cause this issue?

Is that a bumper off headlight out job? 

@Tomlin8 - You should be able to check if there's oil down there by taking off the lower of the 2 intercooler hoses, and I think you can do that in the RHF wheel arch. If oil doesn't run out I'm definitely wrong!

Have you checked the hoses under the inlet manifold? They can be a right git to get at though. Would need to remove the front perforated cover that goes around the dipstick to get at them. One of mine had split on the end where it goes onto the barb on the manifold, kept getting random EML lights as well.

I'll check both tonight. Much appreciated gents 

I've just been browsing some of the threads on here as you do, and came across the piping layout for the engine....my car doesn't have the red pipe I've labelled as "A".... it has a blanking plate on the air box?? It was like this when I bought it, can this pipe be taken off??

I need to check nothing else has been removed

 

 

@Tomlin8 - On the basis that the red pipe connects to 20, the secondary air pump, then yes it can be removed, in fact it's a fairly common modification and doesn't normally cause any problems. Quite the reverse; it's normally done to cure noisy cold running!