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Re: Weak spark. Bit long post Looking for an answer.. Posted by Dana [Email] (#2822) [Profile/Gallery] (more from Dana) on Sun, 10 Jul 2022 12:26:41 In Reply to: Weak spark. Bit long post Looking for an answer.., Bobwithasaab, Mon, 4 Jul 2022 18:45:20 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Going on the only thought of weak spark.
I think in terms of basics. The ignition coil has a constant 12VDC applied to the + terminal of the coil during starting attempt. Each time a spark plug is to fire, the coil +15 terminal is grounded to the engine block voltage (negative battery voltage) which powers the high tension coil to fire. The grounding of terminal 15 is done by the ignition module based on pulses received by the module from the hall effect transmitter. If the spark is "weak, i.e. not enough to start the engine, then possible items are the coil, the ignition module, hall effect generator, spark plug wires, rotor, distributor cap, and proper grounding of the engine and coil to the battery negative. With the right tool, one could see if the coil has pulsing voltage between 12V (coil is not energized, 12VDC is being read through the coil, the 15 terminal is not connected to ground) and when the ignition module connects the 15 coil terminal to ground (0 volts DC). From what I've read, you have changed out much of these devices except the coil itself.
1. Make sure the battery negative cable is firmly fixed to the engine block.
2. If you can read the pulsating coil voltage on the negative terminal, it will tell a lot.
3. Make sure the coil the coil body itself is grounded to the car body electrically.
The very best of luck, it will end up being a simple solution when found.
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