Hoping someone can give some clues to solving an ongoing problem with my Disco 2001 TD5. I have searched the threads on this and other sites but none give a conclusive answer.
For a while now I have had what appears to be a misfire on perhaps one cylinder that comes in at 2100 revs. This stays until the revs reach about 2600 revs before appearing to smooth out and the engine fires on all cylinders. During this band of revs the engine takes on a lumpy rumbling tone and vibrations run through the bodywork. The motor has 116,00 miles on it and is the 10p engine.
There are no faults showing on Nanocom. (other than EGR) So far I have changed again the injector loom, the EGR was removed/blanked when I first got the vehicle, all oils are fresh as are all filters, I have rewired the engine loom directly from the ECU to the injector loom plug under the cam cover, recently removed and cleaned all the injectors, fitted new injector copper washers and O rings, new battery fitted. Checked the auto gearbox flex plate for cracks but all seems ok, released the exhaust rubber hangers and moved it about but with no change, fitted new engine mounts, no oil in loom or ECU, tried another ECU, checked the throttle track/voltages with Nanocom all seems well, checked the front crankshaft harmonic balancer/damper (slight play in it but only a tiny amount). When I was rewiring the engine/injector loom I disconnected one injector at a time and all seemed to have the same effect on the engine and could not see or hear any cylinder having a distinct effect on the misfire. Running out of ideas that don’t involve lots of expense.
Not yet done a cylinder pressure test owing to the difficulty of the job and having the right kit. Also cannot test No 5 pot as has no glow plug. Cylinder balance though shows up ok on Nanocom.
The engine does this when driving and also stationary in Park and Neutral, no smoke or soot from exhaust, same when engine is hot or cold. Is no worse when under load and overall does not seem to lack power.
Any sensible ideas anyone?
For a while now I have had what appears to be a misfire on perhaps one cylinder that comes in at 2100 revs. This stays until the revs reach about 2600 revs before appearing to smooth out and the engine fires on all cylinders. During this band of revs the engine takes on a lumpy rumbling tone and vibrations run through the bodywork. The motor has 116,00 miles on it and is the 10p engine.
There are no faults showing on Nanocom. (other than EGR) So far I have changed again the injector loom, the EGR was removed/blanked when I first got the vehicle, all oils are fresh as are all filters, I have rewired the engine loom directly from the ECU to the injector loom plug under the cam cover, recently removed and cleaned all the injectors, fitted new injector copper washers and O rings, new battery fitted. Checked the auto gearbox flex plate for cracks but all seems ok, released the exhaust rubber hangers and moved it about but with no change, fitted new engine mounts, no oil in loom or ECU, tried another ECU, checked the throttle track/voltages with Nanocom all seems well, checked the front crankshaft harmonic balancer/damper (slight play in it but only a tiny amount). When I was rewiring the engine/injector loom I disconnected one injector at a time and all seemed to have the same effect on the engine and could not see or hear any cylinder having a distinct effect on the misfire. Running out of ideas that don’t involve lots of expense.
Not yet done a cylinder pressure test owing to the difficulty of the job and having the right kit. Also cannot test No 5 pot as has no glow plug. Cylinder balance though shows up ok on Nanocom.
The engine does this when driving and also stationary in Park and Neutral, no smoke or soot from exhaust, same when engine is hot or cold. Is no worse when under load and overall does not seem to lack power.
Any sensible ideas anyone?