My 2yr old 110TDI Octy becomes hesitent under moderate acceleration sometimes.

I have told the dealer about this and he replaced the fuel filter saying it was clogged up completely (at the 20k service). After the service the car ran ok for the first 2k or so, but now the hesitation is back.

It was most noticeable at around 2,000 rpm in 2nd gear before the service (under normal/ moderate acceleration), but now is most noticeable around 2,300 rpm in 4th gear.

I have only ever filled up at sainsburys, and have started using millers diesel plus on occasions to rectify the problem. However, it still happens and is starting to pi$$ me off.

Could this still be the fuel filter? and if so how difficult is it to check (for me).

I thought it seemed more like a problem with the ecu because it is happening at the same revs, but it doesn't happen all the time.

Any advice would be greatly recieved.

JD

Often changing the filter is not enough, you generally could do with wiping the area down where the fuel filter is fitted, then putting 1/2 a bottle of redex in the fuel filter before replacing it. She will take a while to start, but she will feel a lot better once it is cleared out !!

It's not another MAF sensor / turbo pressure sensor pipe problem is it?

It's not another MAF sensor / turbo pressure sensor pipe problem is it?

I honestly don't know. The problems i have heard about before with MAF sensors seem to be prolonged loss of power, where as mine is like an instant where the engine seems to be starved of fuel. It is only a split second, but enough to notice.

If i have reported the problem during warranty and nothing is found/ done about it and then after warranty something goes really wrong, say with the fuel pump, do i have any comeback if i had previously told them about the problem?

I am worried incase it is the fuel pump or the ECU and the dealer is dragging their heels.

Often changing the filter is not enough, you generally could do with wiping the area down where the fuel filter is fitted, then putting 1/2 a bottle of redex in the fuel filter before replacing it. She will take a while to start, but she will feel a lot better once it is cleared out !!

Andy, it was the dealer who changed the filter about 3k ago, and since then i have only filled up with sainsbury's diesel, and used millers every 3 or 4 fills. Surely the filter shouldn't have blocked up again. If it had blocked would it not cut the fuelling at random revs??

JD

I had exactly same problem, fuel filter hept clogging. ended up i had got a dodgy

fill up somewhere and the diesal was really really dirty strangely enough i am 99% sure i got the dodgy fuel from sainsburys dunstable, they once put diesal in the unleaded tank-it cost them a fortune!!

Now i iknow this sounds strange but what i did was clean fuel filter ran the car nearly dry, re cleaned filter and filled the tank with decent diesal (bp ultimate) gave it a good thrash up motorway-50 miles then added half a gallon of petrol and then went on a long drive (200 miles) on the motorway then again filled up with bp ultimate the fault has not re-occured since in 20,000 miles...

i did check the filter after 5K and it was as clean as a whistle...

G7PKF

then added half a gallon of petrol and then went on a long drive (200 miles) on the motorway then again filled up with bp ultimate the fault has not re-occured since in 20,000 miles...

Did I read that correct? Petrol in a diesel car? Maybe I'm a bit too new to the diesel world, so could you explain the benefit of that.

It

I think i will take it to a friend of mine and get him to check it over. He has been a vw mechanic for at least 7 years now. I don't trust the dealers, they keep fobbing me of.

JD

Did I read that correct? Petrol in a diesel car? Maybe I'm a bit too new to the diesel world, so could you explain the benefit of that.

A very small amount of petrol. if you lived in a very cold country where fuel was a premium they sometimes add parafin or a small amount of petrol to "thin it down" i also have a friend who has run hi diesal (old citreon that cost him

I had a hesitation problem with mine a little while ago. I removed the MAF and gave it a good clean with electrical cleaner and refitted it. It was much better with the hesitation gone, but I didnotice a lack of power. I had it rolling roaded not that long ago and it was down by 12bhp. I have since replaced the MAF and she now flies again with no hesitation whatsoever.