This has been an intermittant problem since I have owned the car (2 years).

 

A few months into my ownership I:

 

De-carboned the valves

 

Replaced all injectors

 

Replaced all coil packs

 

Replaced PCV valve

 

Replaced spark plugs.

 

The problem has become more frequent in recent weeks, occurring previously once every couple of months, and now its a few times a week.

 

I turn the ignition on, fire the engine up. It always starts first time.

Once started, the revs drop and it feels very lumpy, almost like its running on 3 cylinders. It won't rev cleanly, but will rev roughly, again feels like a lack of cylinders but that is just speculation.

 

It throws no fault codes at the moment, and hasn't for ages. But has occasionally thrown one about running lean - I think it is an air leak as nothing else is wrong.

 

Very occasionally the car then stalls, and I have to restart it and rev it a bit.

 

Driving it slowly causes it to kangaroo a bit up the road, but as soon as I've driven a minute or so, it drives smoothly and has full power.

 

It happens from freezing cold and luke warm, has typically been a problem on very cold mornings.

 

Given I have replaced all the obvious things, and it runs perfectly once warm... And throws no codes, I don't know where to start. But do suspect an air leak of some kind that warms up and seals itself.

Mmm. Bit mysterious. Throttle body? I had a 2011 vrs for 5 years and can only think of maybe 1 or 2 times it spluttered and stalled. So definitely not normal.. 

As soon as I read it, I was thinking carbon build up or injectors, but have you used genuine injectors? Without sounding rude you didn't get them off ebay or anything

 

 

All genuine parts 

Try throttle body basic settings. Does it complete successfully.  can you hear the butterfly valve move through required range? 

Not sure how to do that without VAGCOM.

 

my mechanic said it may well be the MAF

 

it does smell rich as hell sometimes when I start it, and occasionally get a bank 1 rich ecu code 

Anyone got a spare known good MAF before I spunk £100 on one?

Anyone tried this hella MAF?

I swear there used to be a lot more tech guys on this board.

 

anyway, I managed to catch the engine misbehaving. I pulled the plug off the MAF in time and the revs smoothed out.

 

 I replaced the MAF yesterday with the hella part from GSF. 
 

Car has started perfectly since, and is noticeably more responsive.

 

just need to get underneath and rip off the rattling heat shield and that should be it for a while.