stuttering under acceleration

[Skii]

Hi peeps

More issues with my lemon (sorry I meant my 2004 FR TDI)

Under heavy acceleration I can feel what seems like clutch slip but its almost like I'm lifting off in tiny increments as I accelerate , I don't think its clutch slip because the clutch isn't even a year old and the gear box and clutch were stripped last month and checked. (Car isn't remapped either )

Best description is it feels like the car is stopping accelerating for a series of microseconds

Any clues ?

 

[MJ]

Possible turbo problem or egr issue.

 

[Seatmann]

MJ, is there not some sort of antishudder valve on the tdi's or is that something different?

 

[MJ]

MJ, is there not some sort of antishudder valve on the tdi's or is that something different?

Its only there to give a smooth engine cut off, it operates when the ignition is turned off to choke the engine of air.

 

[Goz]

Hi MJ,
I had a post a few weeks ago which I mentioned the the car made a shudder when I turned the ignition of and you mentioned the antishudder valve. What fault with the ASV would cause this? I have cleaned the EGR already but am also getting stutters when driving at over about 1500 rpm and lots of black smoke when accelerating hard (dirty turbo?).

cheers

 

[sssstew]

skii - if its under heavy acceleration then i would probably rule out EGR as that only works on light throttle. This could be a boost or MAF related issue, get it on VAG COM and log boost and MAF requested vs actual and see what its doing.

GOZ - you have a few symptoms there. if you have an engine shudder at shutdown then its likely a faulty ASV, just swap it out, its a small electric valve at the back of the EGR, its not maintainable. If you have stutters and black smoke when driving then this sounds more like a turbo issue, you need to log the boost and see what its doing.

 

[AndrewJB]

Try fitting the £2 Skoda Gasket to the EGR that solved stuttering issues i had with my 2008 PD170 Leon! i know its a long shot but for £2 you carnt really go wrong

 

[Skii]

skii - if its under heavy acceleration then i would probably rule out EGR as that only works on light throttle. This could be a boost or MAF related issue, get it on VAG COM and log boost and MAF requested vs actual and see what its doing.

Cheers Stew, thanks for the advice - will do

 

[Skii]

hi guys

I thought I'd update this topic with the cause of the problem - Tesco diesel.

The problem lasted as long as the full tank which I didn't refill untill the fuel light came on, filled up from the local Murco and the problem vanished, haven't had a stutter since.

Anyone else had a dodgy tank of diesel before ?

 

[MJ]

Yeah me.

Supermarket fuel uses alot of detergents to Make the fuel go further - this reduces the cetane rating.