tfsi wont tick over ?

[4/4 dirty dervs]

i recently had a problem with my cars revs sticking .. but now when its warmed up on tickover now the rpm sticks at 1250 and then every 5 seconds or so itll increase to 1500 and then drop back down a couple seconds later and then repeat. i also have oil on the rocker cover looking like its coming from the rear pcv and oil cap so i thought maybe the front pcv was broken. but i couldnt blow air the wrong way down the pipe and also the car coughed and spluttered when i removed the oil cap which im lead to believe means its working ?
sorry for the life story but im really racking my brains on this one and havent got vcds so cant check anything on that either any thoughts would be greatly appreciated . thanks.

 

[Joshkcupra]

Sounds like your front PCV is knackered..

 

[4/4 dirty dervs]

Exactly what I was thinking until it spluttered about when I took the oil cap off... well I think i'm going to take the inlet mani off and have poke about because mines high mileage and I could bet my valves are all in a sorry state needing to be cleaned. then I'll block the front pcv off and see if I have any luck with that.

 

[Joshkcupra]

If you pull off the oil cap it will splutter because you've broken the vacuum.. It would be worth stripping the manifold and giving it a clean out, but I highly suspect it is a faulty PCV.

 

[4/4 dirty dervs]

thanks for the input josh. i blocked the front pcv up and the car now idles fine at 750rpm and seems to run a lot better just as a little side note .. how much mpg do you get out of yours ?? the highest ive seen is 25 and that was a 180 miles at 60-70 and 19 combined .. so im thinking the pcv has been bad a long time.

 

[Joshkcupra]

That's good news then mate, I tend to average 31/32mpg when doing 70mph on an A road or motorway, which isn't too bad for stage 2+