Clicking from the Fuel rail/Coilpacks, Need advice

[YUOnDaGround]

I replaced the A/C tensioner pulley tonight and I fired the tahoe up to make sure everything was good. I noticed an erratic clicking coming from the fuel rail/coil packs on the passenger side. Everytime it clicked the engine would stumble.

Has anyone heard this before? I can't be sure this has anything to do with my changing my A/C pulley however, the only reason I stuck my head on that side of the engine while running was to verify that the tensioner was no longer making any noise.

Thanks for your time.

Bruce

 

[Sasquatch]

It could be a bad coil pack grounding to metal. That would explain the stumble in idle.

Look under the hood at night and look for the electrical arc.

 

[YUOnDaGround]

Thanks I'll have to check it out. I just thought it was odd that when it would click and stumble, the stumble was more noticeable than if I were to unplug a coil.