Lumpy acceleration 1.8t

[gjroe78]

Right, got a full refund on the MAF I bought, I am now thinking it maybe more to do with a pipe split now though as have noticed that the problem only occurs when the car has warmed up( maybe 5-7 min into driving) maybe when the pipes become a little bit more flexible.
Does this sound right or am I being a bellend ?
I have checked te pipes and can't see any splits or cracks though

Another question is what is the smallish silicone pipe that comes off the solid induction pipe ?
Cheers for any help guys

[gjroe78]

Right bit of an update for anyone that cares, had it in at a garage on Thursday and have checked that the maf is ok by ordering a new one off VW fitting it and then testing it( he just sent it back after checking) and they are now 99% sure it's the secondary air pump as it makes a strange noise when starting that alerted him to it.
He has a mate who's scrapping a seat, so should have one to test on Tuesday

[JimBR]

A £17 forge blanking plate will sort that by removing the lot 

[gjroe78]

What does it get rid of ?

[JimBR]

Secondary air pump, the tubes going to the airbox and tip (I think) from the pump, N112 valve, a load of vacuum line,

[gjroe78]

Hmm I'm already running an induction kit and just ordered some new silicone hoses so it's probably too late for that to be honest

[JimBR]

Its even easier if your running an induction kit. None of the silicone hoses you can buy replace anything to do with thw SAI system. You just need the blanking plate and 1/2m of 3mm vacuum line 

It also stops the tractor sound on cold start lol.

[gjroe78]

Oh right, what's the point in the secondary air pump then if it can just be taken off and forgot about then, surely it has a purpose ?

[JimBR]

Pumps oxygen into the cat to lower emissions on cold start. More for the american market I think