NS25C3 1999 nissan, losted fire on top plug

[predator116]

Unit quit fireing on one cylinder was running good shut down for lunch then started back up no power under load runs good with no load. checked and found that top plug has no fire to it? wires look good all fuses are good.?

 

[pvanv]

Re: NS25C3 1999 nissan, losted fire on top plug

No fuse in the ignition system.

You probably have a siamese ignition coil (both plug wires connect to a single coil). If one plug is firing, the other should as well... and and that point, you know that the bits under the flywheel as well as the CD are working.

You can check/reverse the spark plugs and plug wires as per usual ignition troubleshooting, which should help you isolate whether you have a bad plug, etc. Full ignition troubleshooting info is in the Factory service manual.