Occasionally not firing on one cyclinder when starting
Discussion
Hi,
My friend has a Mk2 1.6 Califonia, recently when you start the car it will only be firing on three cylinders, turn the engine off, restart and then all is well.
Now, this did not happen every time, but recently it has been getting more frequent, new leads and plugs over Christmas and the problem went away completely until yesterday when every time the car was started it was only with three cylinders.
There is also a really bad smell, almost clutch like, but as this is when starting the car and not from slipping the clutch when pulling away I am not sure what that might be.
Any thoughts greatly appreciated.
My friend has a Mk2 1.6 Califonia, recently when you start the car it will only be firing on three cylinders, turn the engine off, restart and then all is well.
Now, this did not happen every time, but recently it has been getting more frequent, new leads and plugs over Christmas and the problem went away completely until yesterday when every time the car was started it was only with three cylinders.
There is also a really bad smell, almost clutch like, but as this is when starting the car and not from slipping the clutch when pulling away I am not sure what that might be.
Any thoughts greatly appreciated.
I suppose it depends which two! 
Often what sounds like 'running on 3' can just be a vacuum leak and subsequent bad idle. It's a pretty poor and loose slang term unfortunately.
If you pull a plug lead/coil off one cylinder while running and the idle does not change at all then you have diagnosed that cylinder as not sparking or not fuelling. If when disabling each cylinder one at a time they each affect the idle in some way then it's nothing to do with the spark or fuel of a single cylinder. It's something else.
Often what sounds like 'running on 3' can just be a vacuum leak and subsequent bad idle. It's a pretty poor and loose slang term unfortunately.
If you pull a plug lead/coil off one cylinder while running and the idle does not change at all then you have diagnosed that cylinder as not sparking or not fuelling. If when disabling each cylinder one at a time they each affect the idle in some way then it's nothing to do with the spark or fuel of a single cylinder. It's something else.
There are 2 coils running a "wasted spark" system i.e. each spark-plug fires before the combustion and intake strokes. One feeds 1 + 4, the other feeds 2 + 3. So it's easy enough to test for a dead coil - 2 cylinders will be dead. Not sure how you test for a sick but not dead coil though.
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