Author Topic: One Cylinder Not Firing  (Read 356 times)

rbouch8828

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One Cylinder Not Firing
« on: August 27, 2025, 19:49:35 »
Is there an easy way to tell whether the problem is with an Injector or on the Spark side?
RB

Paul & Dolly

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Re: One Cylinder Not Firing
« Reply #1 on: August 27, 2025, 20:48:53 »
Swop the plug with another one and see if you get improvement.
Swop over two injectors and see if the problem moves with the swop.

Good luck
Paul
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rbouch8828

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Re: One Cylinder Not Firing
« Reply #2 on: August 27, 2025, 21:15:30 »
Thanks Paul
RB

Cees Klumper

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Re: One Cylinder Not Firing
« Reply #3 on: August 28, 2025, 04:40:13 »
Take out the spark plug from that cylinder and see whether it is wet with fuel. If so, it's likely not the injector. If dry, then crack loose the tube going to the injector to see if fuel comes out when the engine is running.
Cees Klumper
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rbouch8828

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Re: One Cylinder Not Firing
« Reply #4 on: August 29, 2025, 17:08:37 »
I don’t know which cylinder it is. I first need to find out which is the one that isn’t firing.
RB

Cees Klumper

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Re: One Cylinder Not Firing
« Reply #5 on: August 29, 2025, 19:08:08 »
To find that out, either use an infrared heat gun aimed at the exhaust manifold connections to each cylinder: the one not firing will be much cooler than the others. Or pull each spark plug lead off the plugs one by one with the engine running. The one not affecting how it runs is your culprit.
Cees Klumper
1969 Mercedes 280 SL automatic
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1961 Alfa Romeo Giulietta Sprint Coupe 1600
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rbouch8828

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Re: One Cylinder Not Firing
« Reply #6 on: August 29, 2025, 19:49:53 »
I was planning to pull the spark plug leads to do that check. Hope it turns out to be a bad plug and not something with the fuel pump.

Thanks!
RB

rwmastel

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Re: One Cylinder Not Firing
« Reply #7 on: August 30, 2025, 14:45:40 »
Yes, pull spark plug leads (safely!) one at a time until you find the one that doesn't disrupt the idle.
Rodd

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rbouch8828

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Re: One Cylinder Not Firing
« Reply #8 on: August 30, 2025, 14:51:33 »
Thanks, will give that a try!
RB

 

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