2001 4-Stroke 115 hp EFI mis-fire on 3 and 4

[papspontoon]

2001 115 hp mercury 4 stroke EFI (SN OT341774)

new injector
new fuel
fuel pressure at 41psi
new spark plugs

new coil on 2 and 3

spark seem weak on cylinder 3 and 4

what I don't understand is 1 and 4 are on the same coil and 2 and 3 are on the same coil. Cylinder 1 and 2 fire fine?????

my understanding is that they both fire on compression and exhaust stroke..

no change i the engine when pulling 3 sparkplug wire off.

any help is appreciated

[EuropeanAM]

Compression Test results: ??

Leadown Test Results: ??

Have you placed a timing light on each plug wire, one at a time to confirm your "fire fine" and "weak spark" determinations?

[papspontoon]

compression test was 150 and it held
timing light showed spark however, when using a spark tester The spark wouldn't jump the gap. when using a spark plug to ground. Orange weak spark

[EuropeanAM]

Could be the plug or the wire.

[papspontoon]

I adjusted the throttle shutter synchronization screw and it leveled out.. that changes 3 and 4 cylinder.... smoothed out good.. who knew. maybe that will help someone

[EuropeanAM]

May have been the problem- though it's strongly recommended that this be done with a synchronization tool connected so that the adjustment can be made "precisely".