04 40tlrc cylinder #1 not firing.

[99yam40]

if #1 pulser output was a problem then I would think it would just not fire when it should,
but I have no idea why it would fire when #2 was suppose to.
it would be nice to find another CDI just to try and see if that made any change.

look at the wiring real close to see if you can see any physical damage where #1 and #2 could jump between

might require pulling the flywheel to inspect all the wiring and check the pulser coils gaps if the testing shows a need to

the timing is con*****ed by the CDI and that wiper on it, so I would think it would move as the throttle plates move or even before they move.
if you disconnect the linkage to the wiper then they can be moved indepenantly

[Hd232smoke]

So I did disconnect the arm from the throttle linkage to the timing arm on the cdi. If I advance the timing manually I can get cylinder 1 to start to fire. Then once i move the arm back to the markers on the cdi for idle it idles on all three for just a second then drops #1. Like i said hopefully the tester will come so I can either find the problem or come back with some better info. As for just testing a new cdi i just might have one i can borrow from a buddy.

[panasonic]

Have a look at the wiring from underneath flywheel to the CDI. That's a good place for wires to chafe with all the moving back and forth with the timing plate.

[zenoahphobic]

It’s very unusual to have a faulty electrical “component “ play up precisely at idle, but perform faultlessly from that to WOT. Can’t see any coil or CDI behave like that unless supply voltage goes too low (or high?) and hits a threshold.
Might be time to check what happens to the 12v charging circuit Including regulator at those low revs. Undoing and cleaning all connections particularly around the regulator, fuse and battery; this maintenance might be overdue.
You are running out of causes, so deeper lateral thinking required.

[99yam40]

Have a look at the wiring from underneath flywheel to the CDI. That's a good place for wires to chafe with all the moving back and forth with the timing plate.

as far as I know this 04 motor does not have a timing plate

[Hd232smoke]

Correct I do not have a timing plate. Quick question... I have noticed that my carbs do not have the rubber plugs that go over the air mix needle...would this cause improper mixture or do I not need these plugs?
Also is it completely necessary to use a dva when testing voltage or can I use my meter to start testing without the adsapter?

[99yam40]

the caps over the pilot screws are to keep people without the proper knowledge from messing with the adjustments ( EPA mandate)

hard to measure and compare voltage if the proper equipment is not used

[panasonic]

as far as I know this 04 motor does not have a timing plate

Well it's not that then...lol

[Hd232smoke]

Just and update:

DVA and ohm tested all ignition components and found nothing. Still waiting to get a buddies cdi box due to the erratic timing I found in the timing light on cylinder 1 but the cdi tested just fine on the dva at crank and at 1500rpm. Everything electrical seems to be fine voltage wise. This is whooping my ass

[99yam40]

let us know if a different CDI solves the problem.
I cannot think of what would cause #1 plug to fire when #2 is suppose to, only at idle.
glitch in the electronics maybe
very strange stuff

[Hd232smoke]

My buddy that works at a Yamaha dealer said that the cdi might have a “dead spot” if everything else seems to work well I will keep it updated.

[Hd232smoke]

Has anyone had any experience with cdi electronics? Wondering if their replacement cdi is worth a damn? Part # 117-63D-04

[99yam40]

My buddy that works at a Yamaha dealer said that the cdi might have a “dead spot” if everything else seems to work well I will keep it updated.

I do not see how a dead spot in the wiper(TPS) could cause #1 to fire 0n #2 TDC and not affect #2 & #3 the same way

[Hd232smoke]

So I have found the solution after testing all possibilities in the ignition system. I got my hands on a known working cdi box and wow what a world of difference. I had completely forgotten what a nice smooth idle on all three cylinders feels like but all seems well now. No more #1 cylinder popping in and out from firing. Thanks all for the help! Now I've got to just go ahead and order one which at the price point they are sucks but gotta pay to play after all it is a boat (bust out another thousand)