3l common rail winds for ages fires then runs fine?
Hi all, having a minor difficulty which had left me scratching my head a little;
Ok so I 2007 3l common rail is winding perfectly fine, and runs perfectly fine (even overtook a car up a hill starting at 60 and still reached my 100 by the top, power is still there?) but over the last few days the amount of time it is winding before it fires is getting longer and longer, and it doesn't hesitate when it does fire it's just bang, it's off, although it does throw the smallest puff of white very diesel smelling smoke when it fires? I'm going to put a new fuel filter on it tomorrow, start simple and because that's the best I can think of, but just wondering in case that's not the fault if anyone might have any ideas?
Ideas so far;
Glow plugs, light comes on for the usual time, goes out she winds and winds, glowed her a couple of times before starting, nothing, then after running it at op. temp shut it off, went away for 10 came back, still winding and winding so I say rules out pre-start temp. Also it is just getting longer each time I start, so cold mornings verse warmer afternoons aka different engine temps don't affect it
Lack of compression
Not having the required compression for initial start up, although this was an out there idea I don't believe it's that due too it runs smooth once it fires, and also as with the glow plug idea once the engine is hot such a small lack of compression wouldn't be an issue
Injector issues
If the injectors aren't misting properly it won't fire properly, however with the engine running smoothly and with plenty of power and most importantly no smoke this is unlikely as well
Pump or rail issues
If the pump is not supplying the correct pressure or the rail is losing pressure, start up will be difficult, but it would also not run smoothly and would probably blow smoke
Pump/rail/injectors leaking (internally?)
One of the more likely more technical causes, that the pump rail or injectors could be losing enough pressure through say a faulty pressure limiting valve on the rail or a faulty pressure relief valve in the pump or an internal seal in an injector? Losing enough pressure to make start up hard but not enough to affect performance?
Lift/low pressure supply pump
Possibility that the supply pump has a stuck open check valve not allowing the system to keep supply pressure and is having to work longer to get the supply pressure back up to spec, and it's coming good once there is some suction in the system making the check valve effectively redundant, or even just a supply pump issue where it struggles to get the fuel up to the high pressure pump to start with but again once everything's running with a good bit of suction in the system it comes good?
Any help or ideas would be greatly appreciated!
Sent from my iPhone using Motorculture mobile app
