Missing ignition on cylinders 4 and 2, please help!

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Stand-in
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Missing ignition on cylinders 4 and 2, please help!

Post by Stand-in »

Fuel is present in sufficient volume and balanced
Compression reads, 150,155,160,155 in order of cylinders
Spark is consistent and timed correctly.
I don't hear anything mechanically wrong with the engine (outside of the chop).

What gives?


Stand-in
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Posts: 23
Joined: Tue Jan 09, 2024 2:46 am
My E21(s): 1977 320i US Manual

Re: Missing ignition on cylinders 4 and 2, please help!

Post by Stand-in »

found the problem, two out of my 4 new bosch spark plugs short to ground instead of arcing.
Stand-in
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Re: Missing ignition on cylinders 4 and 2, please help!

Post by Stand-in »

Not the problem, I'm stumped.
I am afraid it might be air supply, and that the cylinder head, whilst beautify sealing, is not allowing for ingress
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Jeroen
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Re: Missing ignition on cylinders 4 and 2, please help!

Post by Jeroen »

Weird? Spark plug cables checked for correct firing order? Correct spark plugs used?
Regards/groeten, Jeroen
Stand-in
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Re: Missing ignition on cylinders 4 and 2, please help!

Post by Stand-in »

Update spark is fine, so is compression. I have problems with fuel, and potentially vacuum. Fuel injectors were clogged, cleaned them and the car started back up after it had died finally. Anyways, still not running good, I think the WUR is fouled and my fuel distributor is throwing off Permatex gasket adhesive. I had a very dirty fuel system but dropped the tanks about a month ago now and have cleaned it up until were it enters my engine bay. I have a WUR rebuild kit and Distributor rebuild kit coming, also I have a fuel injector cleaner. Presuming it gets it back into stock working order I will check compression again, though I dont suspect problems there as it blew 150 155 160 155, and finally look for vacuum leaks; I can hear something around my intake manifold. I need to measure fuel flow at max throttle vrs spec too.
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uwbuurman
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Re: Missing ignition on cylinders 4 and 2, please help!

Post by uwbuurman »

What is the state of the fuel filter?
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