Dusty_vs
your resident mechanic
- Joined
- Jan 22, 2010
- Messages
- 57
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- Location
- sydney nsw
- Members Ride
- 97 vs excecutive sedan
i would assume that im not the only one that has felt the wrath of s**tty holden coil packs. They have a tendency of failing with little to no warning. I was driving back to sydney from wagga one fine sunday arvo and then my ute started spitting and farting with no warning.. To my joy id blown 2 coil packs and had to drive home from marulan on 2 cylinders (fuel aconomy was horendous lol).
The way a v6 commodore engine gets its spark is through whats known as Direct Fire Ignition, or 'waste' ignition, because each spark plug fires twice every engine revolution. Each coil pack feeds 2 cylinders, as it does, the spark travels out of the coil pack, up one lead, through the sparkplug and earths out to the block, to be picked up by the other spark plug on the same coil pack, and back to the same coil pack.
With that crash course in ignition systems, if your stranded on the side of the road and you blow a coil, pull over and test it the bush mechanic way. With the engine off, remove the 2 leads off the one coil pack and start the engine. If its the problem coil pack, youll hear no change in the way it idles (like s**t). If the coil pack your testing is fine, the rpm will drop and it will idle worse, and youll hear a loud clicking noise from where the spark is jumping between the 2 terminals (its natural path, as noted above). If the coil is fine, turn the engine off, refit the leads and start on the next one the same way.
Once youve isolated the problem to one (or two) coil, and if your lucky enough to have a spare coil pack (a bit over the top but i always carried a spare one, with i think its a 5/16th spanner) then change it.. Done
i must stress how much it hurts when removing a lead with the engine running (i speak from experience lol)
The way a v6 commodore engine gets its spark is through whats known as Direct Fire Ignition, or 'waste' ignition, because each spark plug fires twice every engine revolution. Each coil pack feeds 2 cylinders, as it does, the spark travels out of the coil pack, up one lead, through the sparkplug and earths out to the block, to be picked up by the other spark plug on the same coil pack, and back to the same coil pack.
With that crash course in ignition systems, if your stranded on the side of the road and you blow a coil, pull over and test it the bush mechanic way. With the engine off, remove the 2 leads off the one coil pack and start the engine. If its the problem coil pack, youll hear no change in the way it idles (like s**t). If the coil pack your testing is fine, the rpm will drop and it will idle worse, and youll hear a loud clicking noise from where the spark is jumping between the 2 terminals (its natural path, as noted above). If the coil is fine, turn the engine off, refit the leads and start on the next one the same way.
Once youve isolated the problem to one (or two) coil, and if your lucky enough to have a spare coil pack (a bit over the top but i always carried a spare one, with i think its a 5/16th spanner) then change it.. Done
i must stress how much it hurts when removing a lead with the engine running (i speak from experience lol)