No Spark

[Bucko]

Front and rear cylinder spark plugs are fired by one coil. The engine will run with only one coil functioning. The waste spark system works like this: The cylinder with the burnable charge will get the spark, since the mixture is conductive. The other cylinder has exhaust gas in it, which is not conductive. When the spark energy reaches the firing tip, it ionizes the gasses in the gap. If the mixture will burn, it will allow the spark to jump. This system has been used for around a hundred years. My Camaro has waste spark, just like the Drifter. Dual tower coils, one tower fires the plug on one side of the engine, and the other tower fires the plug on the opposite side. There are 3 dual tower coils. The newer systems use one coil per cylinder, dedicated to just that plug.

A wasted spark system works exactly the same way with one coil per two plugs on the same cylinder.   The plugs fire every two strokes, one of which is on the compression stroke (fire) and one on the exhaust stroke (wasted).  Each coil is triggered by separate, front and rear crank pickups which allows for fine-tuning of firing timing for each cylinder (otherwise, why would two crank pickups be required?)

In any case, here's a snip from the service manual: note how the coil marked '5' feeds both cylinder 1 plugs,  and the coil marked '6' feeds both cylinder 2 plugs.

From Section 15-40 Electrical System of the 2001 Vulcan Drifer Service Manual.

[Troll]

Front and rear cylinder spark plugs are fired by one coil. The engine will run with only one coil functioning. The waste spark system works like this: The cylinder with the burnable charge will get the spark, since the mixture is conductive. The other cylinder has exhaust gas in it, which is not conductive. When the spark energy reaches the firing tip, it ionizes the gasses in the gap. If the mixture will burn, it will allow the spark to jump. This system has been used for around a hundred years. My Camaro has waste spark, just like the Drifter. Dual tower coils, one tower fires the plug on one side of the engine, and the other tower fires the plug on the opposite side. There are 3 dual tower coils. The newer systems use one coil per cylinder, dedicated to just that plug.

[Bucko]

The twin plug system DOES NOT control one cylinder per coil, but rather one front and one rear. It should run on one coil, as long as it's splitting the spark between the cylinders. .

Perhaps I'm misunderstanding what you're saying, but the Vulcan1500 uses one coil to fire both plugs in the same cylinder (so it won't run properly, if at all, on one coil).

[Dustywolf]

Might seem an odd question, but....does this thing have a programmer on it? None of this makes any sense, unless there is a problem with the controller. Just another thought, because I can't see the bike: You wires the coils correctly? The twin plug system DOES NOT control one cylinder per coil, but rather one front and one rear. It should run on one coil, as long as it's splitting the spark between the cylinders. Decades ago, I dual plugged my 98 inch SuperGlide. Initially, I used two coils, one for the right side and one for the left. I replaced the ignition controller with a "single fire" system with 2 pickup coils. That let me run one coil for the rear cylinder, and one for the front. That allowed me to set the ign. timing separately for each cylinder, and use the full voltage from the coils to fire the plugs. The Drifter does not have a single fire system.

It does not have a programmer on it. The spark issue appears to be fully fixed, but now the fuel injectors are spraying too much fuel.

I think it may be the water temp sensor, it doesn't appear to have a vaccuum hooked up to the connection. 

[Troll]

Might seem an odd question, but....does this thing have a programmer on it? None of this makes any sense, unless there is a problem with the controller. Just another thought, because I can't see the bike: You wires the coils correctly? The twin plug system DOES NOT control one cylinder per coil, but rather one front and one rear. It should run on one coil, as long as it's splitting the spark between the cylinders. Decades ago, I dual plugged my 98 inch SuperGlide. Initially, I used two coils, one for the right side and one for the left. I replaced the ignition controller with a "single fire" system with 2 pickup coils. That let me run one coil for the rear cylinder, and one for the front. That allowed me to set the ign. timing separately for each cylinder, and use the full voltage from the coils to fire the plugs. The Drifter does not have a single fire system.

[Dustywolf]

ECU test results?

No codes. 

[chief]

ECU test results?

[Dustywolf]

Yep, so everything's working, bikes cranking great.. but it's still spraying too much fuel for the bike to start. Plugs are still dripping wet... we followed the vacuum diagram.

It feels like every time we fix one issue, another one comes right around the corner. 

[Bucko]

IIRC, there's one in the first fiew pages of the service manual.

[Dustywolf]

Good news, we have spark but now no fuel spray.

Does anyone have a vaccuum hose diagram? Of so, please post it here.

Thanks!

[Dustywolf]

So, good and bad news.

Map sensor vaccuum wasn't hooked up at all, got all new vaccuum lining and that fixed the fuel problem for the most part.

Now, I no longer have any spark. This is bizzare. Went from having strong consistent spark to none.

Will add, anytime I apply slight throttle while cranking it, the starter relay will click.

Anyone have any new ideas?

[Dustywolf]

Fuel pressure regulator works to reduce the line pressure only after the engine starts. It's vacuum controlled. Stuck injectors spray fuel as soon as they have pressure applied to them Injector pulse width is controlled by the fuel map in the ecm, and the cell addresses vary by the coolant temperature reading.

Makes me think it has to do with my throttle position sensor... I'll test that according to manual specs 

[Troll]

Fuel pressure regulator works to reduce the line pressure only after the engine starts. It's vacuum controlled. Stuck injectors spray fuel as soon as they have pressure applied to them Injector pulse width is controlled by the fuel map in the ecm, and the cell addresses vary by the coolant temperature reading.

[Dustywolf]

Update: still figuring out the injector issue.

They do not appear to be leaky or stuck open, but when I try to start the bike they fire an unreasonable amount of gas. And there is a lot of pressure in the return line to the tank, could it be the pressure regulator?

[Dustywolf]

So, I suppose I did a combination of things and now I have strong consistent spark.

Now, everytime I try and start it it'll gunshot or pop but won't full on start. I can see fuel mist leaving the pipes.

Plugs end up dripping wet, what do I do now?

Maybe my injectors are stuck open? Sure seems like it

[Dustywolf]

I'm sure you've tried this, but did the ecu fault code flash anything up?

Only in the past, and it was the fuel pump which I ended up replacing. 

[53Indian]

I'm sure you've tried this, but did the ecu fault code flash anything up? 

[Dustywolf]

Just thinking outside the box.... assuming you have the plugs contacting cylinders, maybe they spark once when you hit the starter but then due to the cranking vibration they lose contact and don't spark?

Good thought, but I have my buddy holding up the bike and pulling in clutch and holding the start button for me. I'm definitely making contact so that isn't it.

Such a weird issue.

[Bucko]

I'd think that's part of my issue (having all the plugs out, or 2 at a time out) but that still does not really explain why it only sparks ONCE when I press the starter button.

It makes me think something is telling the ECU "hey, shut off spark."

Just thinking outside the box.... assuming you have the plugs contacting cylinders, maybe they spark once when you hit the starter but then due to the cranking vibration they lose contact and don't spark?

[Dustywolf]

Just to clarify, the motorcycle 'ground' is 'floating' with respect to a dual fire coil output and is not strictly required for the plugs to fire (except in that it provides an electrical path for a pair of plugs in the same cylinder).  The plugs don't fire from coil to ground, rather the complete fire path is from : coil > wire > plug 1 > motor > plug2 > wire > coil (the same coil) - interrupt any part of that path and neither plug fires.
If you have both plugs out, you need to connect them somehow in order for them to complete the circuit and spark.

I'd think that's part of my issue (having all the plugs out, or 2 at a time out) but that still does not really explain why it only sparks ONCE when I press the starter button.

It makes me think something is telling the ECU "hey, shut off spark." 

[Bucko]

Here is the ign system wiring diagram. I still think you have flooded the engine. The waste spark system relies on at least one clean plug per coil in order to work. If there is no path to ground through an ionized air gap, the spark will not happen.  Keep in mind, the spark jumps from the ground electrode to the positive electrode on one plug and from positive to ground on the other plug. All waste spark systems are like this, whether it's a Honda, a Harley, or a Chevrolet. It may be hard to visualize, but that's how it works.

Just to clarify, the motorcycle 'ground' is 'floating' with respect to a dual fire coil output and is not strictly required for the plugs to fire (except in that it provides an electrical path for a pair of plugs in the same cylinder).  The plugs don't fire from coil to ground, rather the complete fire path is from : coil > wire > plug 1 > motor > plug2 > wire > coil (the same coil) - interrupt any part of that path and neither plug fires.
If you have both plugs out, you need to connect them somehow in order for them to complete the circuit and spark.

[Dustywolf]

Here is the ign system wiring diagram. I still think you have flooded the engine. The waste spark system relies on at least one clean plug per coil in order to work. If there is no path to ground through an ionized air gap, the spark will not happen.  Keep in mind, the spark jumps from the ground electrode to the positive electrode on one plug and from positive to ground on the other plug. All waste spark systems are like this, whether it's a Honda, a Harley, or a Chevrolet. It may be hard to visualize, but that's how it works.

I am not flooding it... because the spark plugs are outside of the engine.

Its a super weird issue, especially now that it's acting different with the new VDS.

[Troll]

Here is the ign system wiring diagram. I still think you have flooded the engine. The waste spark system relies on at least one clean plug per coil in order to work. If there is no path to ground through an ionized air gap, the spark will not happen.  Keep in mind, the spark jumps from the ground electrode to the positive electrode on one plug and from positive to ground on the other plug. All waste spark systems are like this, whether it's a Honda, a Harley, or a Chevrolet. It may be hard to visualize, but that's how it works.

[53Indian]

Not a clue on this one.
No aftermarket accessories like alarm or ignition switch fitted that may have disturbed the wiring?
(I had a similar problem with mine but luckily I had another to swap parts off to eliminate the fault, saves needlessly replacing parts too - know anyone local with a VN1500?)
Also try putting a post on the Kawasaki Vulcan forum, there's some knowledgeable guys on there, as on here.

[Dustywolf]

Got the new VDS in, it changed the behavior of everything. The bike wouldn't spark at all with the kickstand down, etc as soon as I replaced the VDS. it would try to start before even with kickstand down and the clutch out.

Still have that spark issue. Clutch sensor works, neutral switch illuminates, kill switch works, fuel pump was working. Ignition switch working.

To reiterate, it will only spark ONCE when holding down the starter. If you keep holding down the starter button, it will not continue sparking.

Any ideas?