D5 (D5244T to 2005) Flat Spot

[rick250561]

Its happened again

It has happened a couple of time before, but usually as the service approaches, however the car was only services last month.

When driving on the motorway it hesitates slightly as I apply the accelerator from around 2500 RPM. You know when I mean, cruising along when you need to ease off a little as a car comes up in front, and then re-apply as the path ahead clears.

As I say it has happened previously but then cleared once serviced, so what could cause this?

[reesky]

Originally Posted by rick250561

Its happened again

It has happened a couple of time before, but usually as the service approaches, however the car was only services last month.

When driving on the motorway it hesitates slightly as I apply the accelerator from around 2500 RPM. You know when I mean, cruising along when you need to ease off a little as a car comes up in front, and then re-apply as the path ahead clears.

As I say it has happened previously but then cleared once serviced, so what could cause this?

I have almost exactly the same problem, but at around 1500-2000 rpm. Slight judder / flat spot. Noticeable when the engine's colder though, and more pronounced in 4th gear.

Going to try changing the fuel filter and top engine mount (S60 D5).

Also going to try some Millers Sport stuff, which I used to use but recently ran out of.

Post back here if you find anything out, won't you?

[rick250561]

Anybody ?

[hobbyhorse]

Originally Posted by rick250561

Anybody ?

Give us a bit more info Rick, whats been done so far, full engine/trans spec also

[rick250561]

As I said it was serviced last month, other than that nothing.

2004 S60, D5 (163), manual, 130,000 miles

[hobbyhorse]

Originally Posted by rick250561

As I said it was serviced last month, other than that nothing.

2004 S60, D5 (163), manual, 130,000 miles

When was the fuel filter last changed ? (not always picked up on a service)

[rick250561]

Originally Posted by hobbyhorse

When was the fuel filter last changed ? (not always picked up on a service)

It was changed at the last service, I have also checked the invoice to confirm this.

[reesky]

Update: After shoving 3/4 of a bottle of Redex in (Not the best, I know, but it's all I could get), with 45 litres of diesel the flat-spot seems significantly better.

I have a new filter to fit this w/end.

With hindsight this problem seemed to come about after filling up at Sainsbury's in Chaddesden, Derby. The fuel delivery was very slow, as if getting to the end of the current supply.

Let's hope the Redex approach has helped. Suggest you try it to, Rick.

On another note, my DIM has packed up today - but that's another story!

[hobbyhorse]

Originally Posted by rick250561

It was changed at the last service, I have also checked the invoice to confirm this.

Firstly I'd actually have a look at the fuel filter (a main dealer claimed to have changed mine once) to completely eliminate it as this is the kind of inter fault that it often gives. Next check all the rubber hoses associated with the turbo/intercooler, give them a good squeeze, thorough visual inspection, then check for traces of oil around the bottom of the intercooler/radiator. Is there any unusual noises when the fault occurs?