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Osgard22

Member

Registered: 2023-07-14

Posts: 3

Intermittent misfire/cut-out on 2007 Dispatch

Hello, first post here and would hugely appreciate any help.
2007 Dispatch 1.6 HDI, old van but has been fantastic, never failed me and I urgently need to get a few more months out of it as I've just started a new job.
The problem; ever since I got it, every now and then, a misfire. Would miss just one cycle, give a solid clonk as the momentum carried it round, then pick back up and carry on. Would happen once, maybe twice then drive fine. Might not happen again for days or weeks then again, misfire/cut-out, clonk, carry on. Didn't seem to show a fault code, garages basically shrugged and offered to change out parts at hundreds of quid a pop. One garage mentioned a code for "high pressure fuel fault" or something like that.
Recently it's got a lot worse, much more frequent and longer lasting. Can still do longish runs with no problem but then starts to miss, cut out, splutter and threaten to die on me. Not missing once and giving that solid clonk any more as the engine turns it over, more of a misfiring, dying away, loss of power. Black smoke out the back from the unburned fuel. I dip the clutch and rev it, drop a gear, nurse it and it picks back up.
It can give a little skip and a miss at any revs, hot or cold but the worst happens when it's been running for a while and particularly on hills, almost like a tilt switch, even if I back right off the revs as I come to a hill it'll miss and die away. If I put the clutch in and rev it seems rev limited for a few seconds, almost like a limp mode, then picks back up.
Sometimes when it misses it seems to reset the ignition. (I've a dodgy connection on the airbag plug under the passenger seat which gives me a beep and a warning on the panel when I switch on, sometimes when it splutters badly and picks back up I get that coming up as if it's switched off and bump started itself.)
It never fails to start, never shows an engine light. The only other problem is a slight loss of coolant over time. I had that checked out and was told the head gasket was fine and it was likely to be a small leak in a pipe.
I'm right up against it at the moment and this is doing my head in. There's no money for mechanics or new vehicles until this job starts paying off so if anyone has any suggestions for a DIY fix I would massively appreciate it.
Thanks a lot.

tee_cee

Member

Registered: 2016-03-18

Posts: 633

Re: Intermittent misfire/cut-out on 2007 Dispatch

I assume that this has a DPF. In which case there should be zero black smoke, and the tailpipe should be clean.  That would indicate a cracked DPF, maybe due to it being blocked.
I would start by getting it tested and cleaned. But first getting it off and an inspection camera will see if it damaged.

Osgard22

Member

Registered: 2023-07-14

Posts: 3

Re: Intermittent misfire/cut-out on 2007 Dispatch

Thanks a lot for the answer. Busy morning here but a quick internet search shows DIY cleaning is possible. I'll check the price of the cleaning fluid.
To be clear, the black smoke only appears for a few seconds after each of the bad cut-outs. Apart from that it runs clean and well.
Would a dirty DPF explain why it happens often on hills? Again, even if I back off and drop a gear to try and unload the engine. It's so often the hills I even thought it could be a dodgy electrical connection that gets separated when the weight shifts but I've tried wiggling everything I can reach and nothing seems to make it miss.
Anyway, thanks a lot for the tip, I'll explore it.

tee_cee

Member

Registered: 2016-03-18

Posts: 633

Re: Intermittent misfire/cut-out on 2007 Dispatch

My DPF was cracked - when I seen smoke coming from the tailpipe, it was actually soot from the DPF that was being blown out by higher exhaust pressure.
The DPF was damaged by to the continual regens due to worn injectors over fuelling. So rather than being the cause of the problem, it was a symptom.
You could try the fap lite app and see when regens are happening.

Osgard22

Member

Registered: 2023-07-14

Posts: 3

Re: Intermittent misfire/cut-out on 2007 Dispatch

Thanks, an injector problem certainly seems possible.