Diesel Stalls At Junctions After Long Journeys.

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On 3/16/2015 at 3:12 PM, ooGQoo said:

My theory is that around town the fuel flow through the filter isn't that great and fluctuates so it's ok but following a steady 70-80mph M/way drive the fuel flow would be steady and flowing at a high rate, thus when pulling up to a round about or lights and eng speed dropped mixed with that O'ring not sealing the fuel flow back to the tank partially sucks/emptys the fuel filter causing negative pressure and cause an air lock type symptom making the engine cut out.

I think the cranking of the eng & allowing the engine to sit for 5-10mins allows the fuel to be drawn back up from the tank thus reversing the effect!

Your thoughts please guys!!??

This thread is still relevant - it started happening with my 2006 1.8TDCi almost a year ago. First time was after around 100 miles mostly at 70ish, all on motorways. Slowing down uphill on the sliproad from the M60 to the M62 at Simister Island (northeast of Manchester) it just died in the righthand lane. Tried to restart, turned over nicely but wouldn't fire. Recovery to Halifax, for a gig. Tried a few more times and it eventually started. Slept overnight in it (too risky to drive back at night in case it happened again) then went to a local garage in the morning.

Garage diagnosed overheating due to fan problem, found a dodgy connection and fixed it. Drove home confidently, but carefully, no problem. No problems round town for a couple of weeks, then another long haul up the M6 to Scotland - again it died just after pulling in to Tebay services, slowing down uphill into a parking space.

Anyway, after various diagnoses including possible faulty EGR valve, and dying on every long journey, I found this thread. Looking back at when it started, it was the first long journey about three weeks after having the fuel filter replaced during a service, and all the symptoms matched perfectly. By now I've got better at predicting and preventing it, basically slowing to about 50 a couple of miles before leaving the motorway, and keeping the revs up when reaching the stop line at lights. Not always successful, but less scary now!

So I bought a new Mann filter (with the O-ring and the larger seal) and had it changed. The old O-ring looked slightly deformed but, after replacing the filter and seals, and tightening up the collar *really* tight (it had needed a lot of effort with giant water-pump pliers to remove, so the mechanic did it up the same way) and bleeding the air and priming, it started. Then died. Enough times to suggest air was still getting in.

He took it apart again (really difficult again), so I suggested *not* using tools, just doing it really tight by hand. Again it started, ran Ok and died after 20 seconds. Just some more air. Then it started Ok and ran for a few minutes, switched off, started again. Since then I haven't done a long motorway journey (first one tomorrow!) but I have done the sort of driving that would have made it cough a few times. So maybe doing it up too tight deformed the O-ring or the outer seal? Most plastic things with rubber seals say only hand-tight so, fingers crossed!

 

 

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Update - since having the fuel filter cap done up nicely hand-tight, I've done half a dozen long, fast journeys with no issues. After the first couple, where I was still driving defensively and expecting the problem, I got bolder and deliberately drove at full speed until as close as possible to stopping, including a couple of situations where it had previously died. Still no problem, so I'm very happy that the over-tightened cap was the entire cause.