Quick no run question. Coil wire shows pulse but no fire to plugs

[vintagecarlover]

Is this a green wire issue I have? 83 cis coil wire shows hot with timing light but not hot on and plug wires. Thx.

[motorracer]

Bad cap or rotor?

[wwest]

Timing light might be close enough to the coil high side CDI voltage pulse that it is flashing for that, not a HV pulse.

Second though is carbon arc path inside the distributor cap or rotor.

[vintagecarlover]

Inside cap is clean and no getting cdi pulse. If it did I'd get same signal off #1 wire too. Is there a module inside distributer or need to be rebuilt?

[Omegaman]

If you connect 2 x 1.5 volt batteries together to give 3 volts you can connect that into the cdi unit to simulate a pulse from the distributor (green wire) you should get a spark on the ht lead from the coil each time you dab a wire onto the battery.

[juanbenae]

is the dizzy turning when cranked with the cap off?

[vintagecarlover]

Originally Posted by juanbenae

is the dizzy turning when cranked with the cap off?

Yes

[vintagecarlover]

Originally Posted by Omegaman

If you connect 2 x 1.5 volt batteries together to give 3 volts you can connect that into the cdi unit to simulate a pulse from the distributor (green wire) you should get a spark on the ht lead from the coil each time you dab a wire onto the battery.

Are u saying the green wire is bad or Cdi is bad? Or dizzie needs a rebuild
?

[Omegaman]

No I'm saying you can test the cdi unit and eliminate that as being your problem, could also be a bad coil. Can you hear a high pitch squeal coming from the cdi unit with the ignition switch on ? I doubt there is anything wrong with the dizzy...as long as its turning .

[Omegaman]

Have you checked you are getting 12v supply to the cdi at the 6 pin connector ?

[juanbenae]

omega, much like my pops seems to be an electrical engineer.. my old man gets so frustrated talking electronics with me because I only tell him im lost like 3 really important things later...

I hit the main breaker off to change out a light switch.... I only know electricity hurts when not respected...

jb

[vintagecarlover]

I'll check for 12v in am. I have 12v at the 3 fuses on the side of the unit. That's where I got power for the timing light.

[timmy2]

Easiest way to check for switched power to CDI 6 pin is at the white T shaped 2 pole connector just below CDI box. It comes from front fuse box and then goes to blower motor relay. (Red wires in connector)
Power at 3 fuse panel is from alternator B+

[ischmitz]

To OP: can you give us a little better explanation of your issue: from your short statements it isn't clear (to me) what you observe:

- Is the box whining when ignition is on?
- What exactly does "coil wire hot" mean. Do you see the timing light going off while cranking when connecting light to center wire of distributor but not when connecting to one of the 6 spark plug wires?
- If yes have you tried to connect a spare spark plug to the center wire and see if you get spark?

Ingo

[vintagecarlover]

Originally Posted by ischmitz

To OP: can you give us a little better explanation of your issue: from your short statements it isn't clear (to me) what you observe:

- Is the box whining when ignition is on?
- What exactly does "coil wire hot" mean. Do you see the timing light going off while cranking when connecting light to center wire of distributor but not when connecting to one of the 6 spark plug wires?
- If yes have you tried to connect a spare spark plug to the center wire and see if you get spark?
Ingo

Yes hot wire means it's carrying current. Yes put a plug in and funny how it left insulated pliers quickly when I cranked it. It's hot too. LoL.
Kinda figured it out was the rotor button cause although looked new it wouldn't ohm out, had no continuity between blade and inside contact. I ordered new one and it'll be in tomorrow morn and will update this. I didn't realize it's kinda fused and rev limiter too.
Don't remember brand at advanced auto but are those ok to run or not? Any input appreciated.

[vintagecarlover]

Ok. I've swapped coil, rotor button and cap but still no spark beyond coil to distributer cap.
Could the spark NOT be strong enough? Any way to use an ohm meter multi meter to check level of spark? Why else would fire not make it to plug wires? Ground off plug wires? Nothing had been touched to alter ground. Last guess cdi?
Any help would immensely be appreciated. Thx. Mark

[ischmitz]

You can do a poor-man's spark voltage test:

Take an old spark plug wire and connect one end to the coil's HV center output. Then maneuver the other end (bare) towards a grounded surface while an assistant is cranking. Use insulated pliers with leather gloves or similar. And keep the end away from the coil's primary to prevent damage of the CDI box.

The spark from the bare end should be able to jump at least 10mm. If not then you could have a weak output from the CDI box or issues with the coil.

The correct way to verify the CDI box is to check inside for certain wave forms with an oscilloscope. Specifically the primary of the DC/DC converter and the output of the DC/DC during spark generation. Unfortunately, no simple multi meter checks here.

Ingo

[timmy2]

Distributor Cap seated correctly? Plug wires in wrong spot for firing order, easy to mix them up.
Sounds like you are getting spark from the CDI box from the coil with the spark plug test.
For whatever reason the cap to rotor to spark plug wire circuit isn't complete?

[Arts911]

I was talking to Mark . By any chance would a Porsche distributor have a pick-up coil inside ?

And if it goes bad there would be no spark going to the spark pligs.

Good luck Mark. Wish i was closer to help out

[vintagecarlover]

Originally Posted by timmy2

Distributor Cap seated correctly? Plug wires in wrong spot for firing order, easy to mix them up.
Sounds like you are getting spark from the CDI box from the coil with the spark plug test.
For whatever reason the cap to rotor to spark plug wire circuit isn't complete?

Dennis. That's a fact jack. No spark on any plug wire. Has spark on main coil wire to dist. Stops there. Is there some kind of pickup in dist? Also someone said if shim or spacer is shot causing dizzie to drop that can be a possibility. Checking that shortly. I'm just wondering if I have big enough spark? Will check that too. Thx art and Dennis and can't forget the spammer above. I hate u spammers.