Hi, I have an 07 1.9 Mjet, had no problems in the last few month until now.. the car has developed a stutter at around 2k rpm, seemed to just be in 3rd and 4th gear but its now in 5th aswell. It doesnt always happen and doesnt seem to happen if I hammer my foot down. I believe it could be the maf sensor but not 100% sure. Probably have to take it to the garage next week as its still under warranty for a few more month yet.

So anyway is the Maf sensor knacked or is it something else? I also have a TMC tuning box on, the stutter started before this I think but could this have spurred it on more? I dont think it has personally, but I'd like a 2nd opinion.

Thanks

It's quite common on the mjet. seems as if you've released the throttle for a split second when you're driving on light load? This points to the egr valve. Although i cleaned mine out and it still sort of does it. Upon closer investigation it seems my waste gate is partially opening on light throttle and stuttering the boost. It is probably a combination of both egr and waste gate in my case.
Hope this helps. Search for egr symptoms to find out more.

Probably EGR mate... i disabled mine through programming and the juddering disappeared.

I haven taken the tuning box off, and the this seems to be the problem, I dont get any stuttering with it off, however once its on its back again. I havew tried turning the power down, and that hasnt helped.

Could it possibly be a faulty box? I am still going to clean my EGR when i get a chance and also replace the fuel filter as they were on my list of what could be wrong.

I have taken it to the dealer and they ran diagnostics on it and it came back with nothing, although the box was off when they did it (for warranty issues).

I seem to experience this intermittently too but do not have a tuning box fitted. I was hoping to just put up with it for now until I get the car serviced next and get the EGR cleaned. I find the car runs differently almost every time I use it, sometimes it really smooth and a nice drive other times it feels a bit lumpier.