Author Topic: Ignition issues  (Read 2187 times)

minger

  • Newbie
  • Posts: 8
  • Location: Cleveland Ohio
Ignition issues
« on: 13 July 2005, 07:46 AM »
Chock full of questions since I found this wonderful site.
The 450 with a gasoline V-8 with what I think is an ignition problem.  Sometimes she has a rough idle and lugs badly.  It happens intermittently making it more fun to diagnose.  New or relatively new: plugs, coil, plug wires, distributor, and points.  Yesterday when I started her after not running several days, she was missing badly.  I pulled the plug wires one at a time and at least 3 cylinders had no effect when the wires were pulled.  As I was replacing the wires on the distributor cap, sometimes it seems as if the pressure on the cap made the car idle better.  Maybe I was hearing things.  But once she warmed up after maybe 10 minutes, the miss started disappearing and then it ran fine.
Other times, I have had no spark out of the coil and after spending time checking all the connections which are fine, I try it again, and the spark returns and she runs fine.  
I am unfamiliar with this transistorized ignition system.  I find these cars can be tough because the systems are neither completely electronic (no prayer of working on them then) nor completely mechanical but an awkward hybrid which makes it more of a challenge.  
Just curious, can any testing procedure for the transistor system?  I have an oscilloscope if that helps.  
Other ideas and suggestions?
Thanks.

tinker

  • Newbie
  • Posts: 8
Re: Ignition issues
« Reply #1 on: 01 August 2005, 10:02 PM »
Quote from: "minger"
I pulled the plug wires one at a time and at least 3 cylinders had no effect when the wires were pulled....I am unfamiliar with this transistorized ignition system.


If you have the transistorized ignition I don't think its a good idea to pull the plug wires when the engine is running as it might damage the system. I used an inductice timimg gun to check if the leads are firing.

For my 280SE there is an indepth test procedure contained in the online manual. I highly recommend checking it out and puuting your oscilloscope to use.
1977 280SE Loaded
West Coast USA