Jump to content

Recommended Posts

'75 2002, stock ignition system (no ad-ons).  Only deviation from stock is a Bosch blue coil.  

 

What's been checked:

  • points, plugs, cap, rotor, condenser and plug wires are new
  • Point gap is correct at .016
  • coil was tested for resistance and is within specs
  • +12 volts at the coil's low tension terminal
  • tried a second Bosch (black) coil; no change

 

Symptoms:

  • no spark at all, using a new spark plug connected to #1 plug wire and resting on the valve cover

 

Questions:

  • Should I be using the OEM resistance wire to power the coil or is that diminishing the voltage at the (blue) coil since it has built-in resistance?  And if that's the case, where do I bypass the resistance wire (i.e. where does it start so I can cut into the harness and replace it with a regular wire)
  • There's a bundle of three wires inside a blue sheath.  I know the two black wires go on the negative coil (#1) terminal--one to the distributor, the other to the tach, and the third clear insulated resistance wire goes to the positive coil terminal (#15).  Where does the other black wire go?  It's by itself in a second, smaller blue sheath and AFAIK was connected to the positive #15 terminal.

 

Help!  Trying to have a running car in time for this weekend's Spring Drive in northern KY.

 

Dene

Link to post
Share on other sites

Pull the centre HT lead off the distributor, hold the rubber part and direct the metal end close to a metal engine part: do you get a spark then you disconnect either low tension wire from the coil (ignition on)?  If yes, coil & wiring good, if no then coil or wiring bad.

If yes, then take a look in the distributor: are points opening& closing as engine cranks? Is the rotor arm in good condition? Try changing condensor.

 

Link to post
Share on other sites

With the Bosch blue 3 ohm resistance coil you don't want the original resistor wire. The resistor wire goes about 3 ft into the harness, around middle of the firewall. It feeds from the #4 fuse but isn't fused.

 

The only other wire than the green power wire on the positive  15 terminal should be a black/red wire going to the starter for voltage boost while cranking.

 

I would also suggest trying another condenser, I've had a few duds brand new.

 

Check your ground connections too.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...