18 MPG.... Yuck.. 1985 Vt1100

[Snow Shadow]

Could be your pulse generator for that cylinder. if ther's no spark and the coils are good. Or could be just a bad or dirty connection.

[Dartmech]

The manual says there are crank/ignition pulse generators and camshaft pulse generators. But it does not say why or what they control... The ignition module gives the signal to the both connectors but I haven't found what gives the ICM its input yet. Both connections have power (Black/white wire) with the kill switch on.
The blue wire from the connector tee's of and goes to the Spark controller 1 and fuel cutoff relay.
I'm tired and may be over thinking it at this point but if the fuel pump runs, being controlled by the fuel pump relay, and the relay switches on by the blue wire, getting its signal from the ICM-tying into the connector for the front coil, then it should be working....
Dang almost confused myself on that one..
Until tomorrow.

[Inferno]

Time to check resistance on all your pulse generators.

[John Hopkins]

Originally Posted by Dartmech

I cleaned the float valve, jets, inline filter to the float valve. Everything is working as it should now. Still no cylinder. When I cover the intake fuel starts going all over my hand so we have fuel flow now.
The spark from the "Left" cylinder, which I mentioned was weak, is now gone. All the plugs have been replaced, I swapped the coils/ plug wires for each cylinder and switched the RED and WHITE connectors under the seat. The Left cylinder coil will fire the right cylinder. Coils are good.
Whatever part sends the signal must have been getting weak, and now that I've messed with it, finally went dead.
The Red connector, plugged in or not, makes no change.

It looks like I had a couple of problems here. Fuel is solved. Cylinder is wet.
I need to find where the RED connector gets it's signal and go from there.

Thanks for all your help guys!

I've got to come back in here to ask one question based on the above statement..

Fault:: No spark to left cylinder...

spark ok to right cylinder...

what you know..all spark plugs are new..right coil works, right HT lead works right plug cap works..

What you don't know Left coil?? left HT lead??? left plug cap??

What you have done...

Tersted left coil by swapping to right...coil works...

What haven't you done ....tested left HT leads or plug caps..or have you?

John.

["Captain D"]

LLLL, I`m confused now...

I ain`t no mechanic, I just work on everybodys Bike, fer those that can`t afford a mechanic...

Good Luck Dartmech,
Dennis

[Dartmech]

I swapped the function of the coils/wires/caps. I switched the red/white connectors, then the spark plug wire (HT wire) sets to each cylinder. Think completely removing the coils and wire sets and swapping them to the other cylinders. Everything related to the left cylinder(dead) would fire off the right perfectly. The Right cylinder components stopped working on the left.
I am confident that the Ignition system, as far as the coil/wire/caps/plugs are concerned, is operational because as long as either set is hooked up to fire the right cylinder, they do.
The problem is the BLUE wire in the RED connector for the left cylinder ignition signal.
I'm in the process now of tracing down the pulse generator connectors to ohm but I haven't located all the connectors I need yet.
Does one pulse generator control one cylinder? That seems odd to have an independent ignition system.

[John Hopkins]

Originally Posted by Dartmech

I swapped the function of the coils/wires/caps. I switched the red/white connectors, then the spark plug wire (HT wire) sets to each cylinder. Think completely removing the coils and wire sets and swapping them to the other cylinders. Everything related to the left cylinder(dead) would fire off the right perfectly. The Right cylinder components stopped working on the left.
I am confident that the Ignition system, as far as the coil/wire/caps/plugs are concerned, is operational because as long as either set is hooked up to fire the right cylinder, they do.
The problem is the BLUE wire in the RED connector for the left cylinder ignition signal.
I'm in the process now of tracing down the pulse generator connectors to ohm but I haven't located all the connectors I need yet.
Does one pulse generator control one cylinder? That seems odd to have an independent ignition system.

The pulse generator is like a wheel of magnets which of course rotates as it rotates it passes a head rather like a tape recorder head, this has two wires attached to it, for each cylinder, each time a magnet passes the heads it sends a pulse up each pair of wires..although it is possible for you to have a faulty pulse generator that would stop the pulse from travelling up one pair of wires and not the other, it is unlikely..usual faults include things like a dislodged head which has moved too far away from the wheel or a bent mount which has caused the head to hit the wheel..or a broken wire...without getting too basic..sometimes a wire can break inside the outer insulation and the outer can hold it in place until it is dislodged by vibration.. pulling the outer sleeve of a wire at crimp points or bends can show this by the way the wire stretches..

I've written that badly the heads are mounted one at the top and one at the bottom of the wheel..

John.

[Dartmech]

I see what your saying and understand the principle of the generators. Your saying the pulse generator is less likely to fail. It's more likely the wiring has broken or become open in the circuit somewhere. Correct?
I'm headed out now to get back at it. Hopefully I'll have more information when I return.
Thanks.

[Dartmech]

Ohm checks passed on EVERYTHING... The cam and two crank pulse generators show pulsing with a test light.
With the one cylinder running the signal wire to the coils pulses, the signal wire on the dead cylinder is steady on.
There is continuity from the red plug to the spark box.
All signs are pointing to the big Spark box next to the battery being defective/ not distributing the signal to the forward coil, just staying on.

[tcanthonyii]

That sucks dude. Start searching ebay for a new one!