Intermittent misfire on 08 Corsa D diesel ecoflex

[Ed/L152]

I'm looking for some pointers into diagnosing a problem with an intermittent misfire on a Corsa D 08 diesel ecoflex 105,000 miles, please.

It started the day after I had the EGR replaced, lasted for a few hours, then was fine for months. Happened again last month for a few days with injector circuit fault codes on cylinders 1 and 4 (P0201 and P0204) then again a few weeks later with the same fault in cylinders 2 and 3. I filled it with BP Ultimate Active diesel, then it was fine. Filled up again with Ultimate last night and it's misfiring worse than ever - at times it felt like it was running on just one cylinder. Whilst it's misfiring the EML is lit and it clears a few seconds after the misfiring stops. There's no apparent pattern to it, tickover or under load doesn't make any difference, although it seemed not so bad once it had warmed up. It starts fine, even if it's misfiring immediately.

There's no fuel pressure fault codes, and fuel pressure ran at around 16000Kpa during the episodes of misfire. Nonetheless I'm having the fuel filter changed today because it's a easy start and I don't think it's ever been done, but I'm not holding out much hope.

If it doesn't resolve the problem, any ideas where to go next, please?

Edited by Ed/L152 on Friday 16th February 10:12

[227bhp]

Wait to see if it does before wasting peoples time.

[Ed/L152]

Thanks for your help. It's still misfiring after changing the filter but I'll see how it goes for a couple of days.

[227bhp]

That was quick. I doubt it will clear if it hasn't already, what did whoever change the filter say?

[Mr2Mike]

A dirty fuel filter will not cause an injector circuit fault. Sounds far more like you have some wiring problems.

[Ed/L152]

Thanks everyone. Mechanic has suggested wiring problems too, but not very sure.

Edited by Ed/L152 on Friday 16th February 12:14

[227bhp]

I think it sounds like wiring problems.

[E-bmw]

I would get the injector wiring checked.