Electrical problem / popping noise / low spark

[ultrahuck]

I have a '99 Valk with super-low miles  3,500 that I bought about two years ago.  All was fine until about a month ago when I started hearing a popping noise at idle from the right exhaust.  Plugs are new and I rechecked each plug with one of the "old" ones I had just replaced.   When I unplug the plugs on the right side one at a time, there seems to be no diff. in rpms on the engine and each of those plugs are wet with gas when I remove them after the test, BUT there IS some spark going to each of those cylinders when  I do the screwdriver test BUT I don't know if there is full spark.

Boiling down to, how can I check if my coil is not putting out enough spark for one side of my engine? 

OR, anything else you can offer in help?

The engine at higher rpms seems to run pretty well.

Perplexed with this popping problem,

Tom

[salty1]

Sounds like you could have slow speed jet issues. I seriously doubt you have  coil problems. The wt plugs were probably fouled. Change out the plugs and make sure the battery is fully charged. Take it from there and see how it's running. FWIW 

[BobB]

Each of the three coils handles a cylinder on the right and left bank of cylinders.  I don't think that a coil could be your problem if you only report problems on the right bank...

[Pappy!]

Would check Pilot screw adjustments and carb sync before I would spend alot of time chasing electrical/ignition issues.
But........
Pull plug wires, one by one, and get a feel for which ones have the most rpm drop vs. which ones do not or barely make a difference. This can lead you to which cylinders need to be looked at. The ones with the most drop are the ones that are running right.
You can check spark on each cylinder fairly easily with an inductive timing light, if you have one.
If not, get an extra spark plug. Leave the old plugs in the cylinders and check each cylinder with the old plug laying on the head hooked up to individual spark plug wires. or if you have a good ear just pull each plug wire to the end of the cap and listen and watch for the spark.
Believe all this will be futile though. Betting your issue is in fuel/air mix or carb sync.

[R J]

When was the last time all the little hoses were replaced?

Has it been DeSmogged?

that is where I'd start.   IF you do replace any hoses, cut them to the exact same length.      NO longer, NO shorter.

NO fuel pump so the gas has to always run downhill, no back up a little and then down again.

[R J]

When was the last time all the little hoses were replaced?

Has it been DeSmogged?

That is where I'd start.   IF you do replace any hoses, cut them to the exact same length.      NO longer, NO shorter.

NO fuel pump so the gas has to always run downhill, no back up a little and then down again.

Keep us posted on progress.

[Bighead]

With only 3500 miles on a 16 year old machine I am with sandy on this one probably low speed jets.
3500 in 16 years what is that about 6/10ths of a mile a day average.
Hell I have ridden 5k in two weeks

[R J]

With only 3500 miles on a 16 year old machine I am with sandy on this one probably low speed jets.
3500 in 16 years what is that about 6/10ths of a mile a day average.
Hell I have ridden 5k in two weeks

I agree with you Bighead, but, let's just do one job at a time, so if for some reason it doesn't run right, we know where to go 1st.

1. Do the hoses.
2. Do the carb clean, Seafoam or something along that line.