Philip730i
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That it’s a mystery!
2009 m139 4.2 Quattroporte misfire
- Thread starter Philip730i
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spkennyuk
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Had a similar issue on a GT a few weeks ago. Slight miss on 2 cylinders and only under load. That was an air leak being caused only when the engine moved on the mounts when under load. In the case of the GT it was the air intake at the plenum. New jubilee clip sorted it. Cable tied in place as a temp fix on the spot.
No idea why it was only 2 cylinders that were showing the misfire.
conaero
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No problem I hope we helped
Philip730i
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Update on the mystery….
Way back from Le Mans high revs battery light on solid, under 3k rpm no issues and showing 13.7v and charging battery.
Time for an alternator
@philw696 has now fitted 2 alternators to it and neither will provide any voltage.
It currently has a brand new Maserati alternator, all misfires and any faults have gone (other than a parking sensor despite changing it 3 times) but no charging….
So no misfire but no charging circuit!
Way back from Le Mans high revs battery light on solid, under 3k rpm no issues and showing 13.7v and charging battery.
Time for an alternator
@philw696 has now fitted 2 alternators to it and neither will provide any voltage.
It currently has a brand new Maserati alternator, all misfires and any faults have gone (other than a parking sensor despite changing it 3 times) but no charging….
So no misfire but no charging circuit!
Philip730i
New Member
- Messages
- 10
It’s all running with no misfires!
New alternator sorted the misfires and after exploring the alternator wiring (removing the inlet manifold) found the signal wire in the grey plug had pushed out of the connector where it was almost impossible to see or feel but enough to not make a good connection
So now it has a working charging circuit and a beautifully running engine
Just for some catalytic converters to get it through emissions test in France and I might get to enjoy it before the next issue arises
Thank you to everyone who helped and pointed in the right direction; cannot thank you enough and this forum
New alternator sorted the misfires and after exploring the alternator wiring (removing the inlet manifold) found the signal wire in the grey plug had pushed out of the connector where it was almost impossible to see or feel but enough to not make a good connection
So now it has a working charging circuit and a beautifully running engine
Just for some catalytic converters to get it through emissions test in France and I might get to enjoy it before the next issue arises
Thank you to everyone who helped and pointed in the right direction; cannot thank you enough and this forum
