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No 2 cylinder not firing
Posted: Sun Jul 05, 2015 9:04 pm
by Unimatrix1066
Just going through jobs to do on my car one cylinder is not firing there is a spark , and there is compression as I ve checked this also no choke is required from cold?
Re: No 2 cylinder not firing
Posted: Sun Jul 05, 2015 9:09 pm
by simmitc
Is it definitely only one cylinder not firing? Are the leads in the correct order? Try changing the plug in case it doesn't fire when under pressure. How have you confirmed that it is No. 2 not firing? What are the compression readings for all cylinders?
Re: No 2 cylinder not firing
Posted: Sun Jul 05, 2015 9:28 pm
by bmcecosse
As above, but also- hold the plug cap 1/8" away from the plug top (insulated pliers...) - does it pick up and start firing now? Also worth checking the valve gaps before testing the compressions.
Re: No 2 cylinder not firing
Posted: Sun Jul 05, 2015 9:36 pm
by Unimatrix1066
I removed other leads and it engine stops , I checked the compression by turning over the engine and seeing if there pressure from the plug hole. It seemed equal to other cylinders
To check the non firing cylinder while the engine was running it removed each lead and only one did not alter the running of the engine
Re: No 2 cylinder not firing
Posted: Sun Jul 05, 2015 9:51 pm
by simmitc
Good basic tests, but may not show some problems. As a next step, try swapping the plugs between 1 & 2 - does the fault stay with 2, or move to 1?
Re: No 2 cylinder not firing
Posted: Mon Jul 06, 2015 10:01 am
by bmcecosse
Did you hold the plug cap 1/8" away ??????????
Re: No 2 cylinder not firing
Posted: Mon Jul 06, 2015 6:15 pm
by Unimatrix1066
I just took each cap off so it was nowhere near the spark plug anode, plus a spark was present on plug when earthed to the block
Re: No 2 cylinder not firing
Posted: Mon Jul 06, 2015 8:37 pm
by simmitc
If you can see a weak spark on the plug, then as suggested before, swap two plugs over and see if the fault moves. If yes, then it's a failed plug, if no, then it's a lead or cap problem (or compression as the test used is not perfect). Can you try the tests suggested by Roy and me, and then report back. Not needing choke suggests a rich mixture, but let's deal with one thing at a time.
Re: No 2 cylinder not firing
Posted: Mon Jul 06, 2015 8:39 pm
by bmcecosse
If you don't try the suggested tests, WE CAN'T HELP YOU....

Re: No 2 cylinder not firing
Posted: Mon Jul 06, 2015 8:47 pm
by Unimatrix1066
I have not looked at it since yesterday so will try the tests suggest , I will not be until the weekend now