Hi, I'm new on here.. recently purchased a 1.9 sharan and its sadly not without issues. I hope somebody can shed some light.

It seems to run quite well and have a good MPG return

however at idle and at lower revs it hesitates. idle is not entirely smooth.



I have tried to and rule out fault MAF as I was getting readings in excess pf 200mg or 50% above specified. When i drove with maf disconnected it ran like of bag of nails. No power and i could barely get past 3000rpm. or 60mph

I also tried the blanking of EGR vacuum pipe but that resulted in stalling.
The EGR was absolutely caked even the entrance to the cooling pipe was almost entirely blocked when i cleaned.

Since cleaning the egr valve i am getting valve either at 84% or 4.4% under throttle it does fluctuate a little in between but only for short bursts and it will be back at 84%

Could anybody please offer some suggestions? intake Pressure actual 1017.9 compared to 1020mbar without engine running and 1043-1050 at idle. Pressure is constant other than when throttle is pressed and appears to peak as it should then settle around the 1500 on WOT 3000rpm




Also note.. emissions pre egr clean were very high. Not got it tested sine/yet.


i'm clutching at straws.
1) Rough running without maf connected is because the EcU is now dependant on EGR? and egr not working as it should so it causes the issue?
2) EGR 4.5 -85% doesnt seem (from my ignorant perspective) to be full range. Although cleaned there is lack of vacuum to open/lose fully.. vacuum leak in hose or diaphragm or solenoid?
3) Stall when vacuum pipe blocked off ie simple delete. has got me. could it be intake manifold is cruded up? As said i cleaned the EGR and it was almost entirely blocked with muck. as was the end of the cooler pipe.
Any thoughts?