Hi all, I have the M51 diesel in a BMW 325TDS (sorry) which has issues.
The engine will start but only for a few seconds, after cranking it chops about between 600-700rpm then jumps up nearer 1000rpm and dies (with a knock), with some light density smoke from the exhaust.
The above symptoms are with the inlet manifold disconnected, which I beleive would discount the turbo (?), there is some oil in the EGR/inlet which I cleaned previously. Also the FIP has been backed off by moving the top sections to reduce fuel quantity which has the effect of stopping it firing at all (back to normal position now).
This started immediately after I had the water pump, thermostat, coolant, aux belt and tensioner replaced, apparently it smoked out a workshop . Since then it's had a compression test which was OK (~400psi on 4-5-6 and just under on 1-2-3), injectors 2 & 3 visually checked OK and glow plugs checked OK. Previously I've replaced the upper two injection pump / FIP seals and all leak off pipes successfully with a good few hundred miles since. Also it's had oil and filters changed a couple thousand miles ago. The MAF sensor recently failed with 'hesitant' symptoms, relieved by running without it, I've since replaced it with a used non-OEM part which has run OK for a few hundred miles. I also suspect the car has been chipped as it was supplied with a microchip in a plastic box.
At present, I think the FIP is the initial candidate (been quoted £170 to test it and £575 for a repair/exchange unit if faulty from Merlin Diesel) however I plan (on Sunday in daylight, hopefully not in the rain) to try bleeding any air out of the fuel lines and disconnecting sensors to see if it has any effect (this would be preferable solution!). I would appreciate any advice you may have regards further tests or suggestions on what might be at fault. In other respects the car is pretty sound, would be a shame to lose it.
Many thanks in advance, Regards, Alex.
The engine will start but only for a few seconds, after cranking it chops about between 600-700rpm then jumps up nearer 1000rpm and dies (with a knock), with some light density smoke from the exhaust.
The above symptoms are with the inlet manifold disconnected, which I beleive would discount the turbo (?), there is some oil in the EGR/inlet which I cleaned previously. Also the FIP has been backed off by moving the top sections to reduce fuel quantity which has the effect of stopping it firing at all (back to normal position now).
This started immediately after I had the water pump, thermostat, coolant, aux belt and tensioner replaced, apparently it smoked out a workshop . Since then it's had a compression test which was OK (~400psi on 4-5-6 and just under on 1-2-3), injectors 2 & 3 visually checked OK and glow plugs checked OK. Previously I've replaced the upper two injection pump / FIP seals and all leak off pipes successfully with a good few hundred miles since. Also it's had oil and filters changed a couple thousand miles ago. The MAF sensor recently failed with 'hesitant' symptoms, relieved by running without it, I've since replaced it with a used non-OEM part which has run OK for a few hundred miles. I also suspect the car has been chipped as it was supplied with a microchip in a plastic box.
At present, I think the FIP is the initial candidate (been quoted £170 to test it and £575 for a repair/exchange unit if faulty from Merlin Diesel) however I plan (on Sunday in daylight, hopefully not in the rain) to try bleeding any air out of the fuel lines and disconnecting sensors to see if it has any effect (this would be preferable solution!). I would appreciate any advice you may have regards further tests or suggestions on what might be at fault. In other respects the car is pretty sound, would be a shame to lose it.
Many thanks in advance, Regards, Alex.
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