!! Help with cross-firing !!

[Boardwaxstyle]

All,
The motor is a sport jet 175

I have figured out most of what i previously posted about. However i am getting cross-firing on all cylinders. Eg cylinder #1 when observed with a timing light indicated the timing marks for cylinders 1,3 and 5. The same pattern was observed when testing cylinder #2 ( the marks for cylinders 2, 4, and 6 were illuminated). Its causing very rough idling and poor starting.

Anyone have any ideas what would cause this?

 

[tdonoughue]

Looks like that is a V6. Didn't know that they had timing marks on the flywheel for other than cylinder 1. Learn something new everyday.

Anyway, my first step on suspected cross-firing has always been to replace the plug wires. Doesn't take much of a crack or weakness to begin mayhem, and a set of wires is just too cheap for me to not try first. Of course, when putting in the new wires, do make sure that you are following the proper wire route for each wire, locking it down if there are brackets for it (and try not to run 2 wires parallel to each other and next to each other).

Does it have a distributor or electronic ignition?

 

[Boardwaxstyle]

Looks like that is a V6. Didn't know that they had timing marks on the flywheel for other than cylinder 1. Learn something new everyday.

Anyway, my first step on suspected cross-firing has always been to replace the plug wires. Doesn't take much of a crack or weakness to begin mayhem, and a set of wires is just too cheap for me to not try first. Of course, when putting in the new wires, do make sure that you are following the proper wire route for each wire, locking it down if there are brackets for it (and try not to run 2 wires parallel to each other and next to each other).

Does it have a distributor or electronic ignition?

Good evening,
The flywheel did not come with marks from the factory. I indexed in cylinder to TDC then marked the flywheel with a paint pen in relation to the alignment marker.

Yes it is a V6. It is electronic ignition with coil packs adjacent to each cylinder. The plug wires are very short, id say less than 6 inches including the caps. I appreciate the recommendation, I will source some oem plug wires. But its worth mentioning the signal wires (green, green/white, and green/red) are routed together in sheathing from the factory for each bank of the motor.

 

[tdonoughue]

Ahhh... so you were well on your way to suspecting something already to have marked the flywheel.

The 2000 Sport Jet 175 I looked up online didn't have packs at the plugs. Still, a bad wire can make for difficult diagnosis. The signal wires are typically lower amps, so I've not yet seen crosstalk on those. However, if they use the same plug along the way, I have seen corrosion or bent pins that have caused shorts or discontinuity issues. So that might be something to check, too.

Beyond that you need to begin suspecting the controller...