Continuously Firing Ignition Coils
Thread Starter
Cruising
Joined: Sep 2011
Posts: 11
Likes: 0
From: Elma NY
Continuously Firing Ignition Coils
The car is a 2004 ZO6
Has anyone ever experienced the coils firing constantly, the car quits running then when checking for the problem with the ignition switch in the run position we noticed a buzzing it was the ignition relay. We change the relay and the replacement buzzed just the same. We also noticed the buzzing seemed to also coming from around the top of the engine. Upon further inspection we found out it was the ignition coils, now remember the engine is not running just the key is on. If we unplug the connectors to both coil packs the buzzing stops even the ignition relay. If you plug in either coil pack or both the buzzing returns. Pulling the spark plug wires and setting them up so they are all close to ground they all fire continuously nonstop all eight just like eight arc welders. We have load checked battery, pulled every ground apart and checked connections, the car is a low millage car that I don’t think has even seen rain.
Has anyone ever experienced the coils firing constantly, the car quits running then when checking for the problem with the ignition switch in the run position we noticed a buzzing it was the ignition relay. We change the relay and the replacement buzzed just the same. We also noticed the buzzing seemed to also coming from around the top of the engine. Upon further inspection we found out it was the ignition coils, now remember the engine is not running just the key is on. If we unplug the connectors to both coil packs the buzzing stops even the ignition relay. If you plug in either coil pack or both the buzzing returns. Pulling the spark plug wires and setting them up so they are all close to ground they all fire continuously nonstop all eight just like eight arc welders. We have load checked battery, pulled every ground apart and checked connections, the car is a low millage car that I don’t think has even seen rain.
Tech Contributor
Joined: Jan 2007
Posts: 19,564
Likes: 1,207
From: Dyer, IN
The car is a 2004 ZO6
Has anyone ever experienced the coils firing constantly, the car quits running then when checking for the problem with the ignition switch in the run position we noticed a buzzing it was the ignition relay. We change the relay and the replacement buzzed just the same. We also noticed the buzzing seemed to also coming from around the top of the engine. Upon further inspection we found out it was the ignition coils, now remember the engine is not running just the key is on. If we unplug the connectors to both coil packs the buzzing stops even the ignition relay. If you plug in either coil pack or both the buzzing returns. Pulling the spark plug wires and setting them up so they are all close to ground they all fire continuously nonstop all eight just like eight arc welders. We have load checked battery, pulled every ground apart and checked connections, the car is a low millage car that I don’t think has even seen rain.
Has anyone ever experienced the coils firing constantly, the car quits running then when checking for the problem with the ignition switch in the run position we noticed a buzzing it was the ignition relay. We change the relay and the replacement buzzed just the same. We also noticed the buzzing seemed to also coming from around the top of the engine. Upon further inspection we found out it was the ignition coils, now remember the engine is not running just the key is on. If we unplug the connectors to both coil packs the buzzing stops even the ignition relay. If you plug in either coil pack or both the buzzing returns. Pulling the spark plug wires and setting them up so they are all close to ground they all fire continuously nonstop all eight just like eight arc welders. We have load checked battery, pulled every ground apart and checked connections, the car is a low millage car that I don’t think has even seen rain.
Thread Starter
Cruising
Joined: Sep 2011
Posts: 11
Likes: 0
From: Elma NY
The voltage at the relay was 12.5 volts it appears that the relay buzzes is because of the huge draw of all eight coils firing continuously, when we unplug the coil packs it stops buzzing. We have checked all the harness that we can see, even under the car by the starter. The is no corrosion anywhere, I am wondering what every controls the firing of the coils is what is bad. The last time that we were working on the car when it happened the car was up on four jack stands we started the car it ran for a few minutes then just shut done and the condition I described started. The car was just sitting idling no one was in the car nothing was being done and it just shut down. We did retrieve the code but I don't have them with me or I would have posted them. We put a battery charger on the battery while we were trying to diagnose the problem and you can tell that with all the coils firing it is drawing a huge amount of power the spark from all eight wires is great it is all that I would expect, just not all eight at once continuous.
Tech Contributor
Joined: Jan 2007
Posts: 19,564
Likes: 1,207
From: Dyer, IN
The voltage at the relay was 12.5 volts it appears that the relay buzzes is because of the huge draw of all eight coils firing continuously, when we unplug the coil packs it stops buzzing. We have checked all the harness that we can see, even under the car by the starter. The is no corrosion anywhere, I am wondering what every controls the firing of the coils is what is bad. The last time that we were working on the car when it happened the car was up on four jack stands we started the car it ran for a few minutes then just shut done and the condition I described started. The car was just sitting idling no one was in the car nothing was being done and it just shut down. We did retrieve the code but I don't have them with me or I would have posted them. We put a battery charger on the battery while we were trying to diagnose the problem and you can tell that with all the coils firing it is drawing a huge amount of power the spark from all eight wires is great it is all that I would expect, just not all eight at once continuous.
Thread Starter
Cruising
Joined: Sep 2011
Posts: 11
Likes: 0
From: Elma NY
I will have to check the latching voltage but I think the relay is buzzing because the high draw of all the coils. If I can figure what is causing the coils to fire I think it will take care of the buzzing relay. If we unplug the coil packs relay works normal.
Tech Contributor
Joined: Jan 2007
Posts: 19,564
Likes: 1,207
From: Dyer, IN
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From: Rantoul IL
Thread Starter
Cruising
Joined: Sep 2011
Posts: 11
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From: Elma NY
I will post the information as soon as I get it the car is not here with me. I just thought someone may have run into this before, I am sure the latch voltage will be the same as the battery voltage because every connection I have checked is perfect but did not want to say that until I actually checked it. Also as I said if I unplug the coils the relay works normally.
Melting Slicks
Joined: Jun 2010
Posts: 2,809
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From: Yorktown Virginia
I will post the information as soon as I get it the car is not here with me. I just thought someone may have run into this before, I am sure the latch voltage will be the same as the battery voltage because every connection I have checked is perfect but did not want to say that until I actually checked it. Also as I said if I unplug the coils the relay works normally.
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From: South Western Ontario
4th Gear
Joined: Aug 2021
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The car is a 2004 ZO6
Has anyone ever experienced the coils firing constantly, the car quits running then when checking for the problem with the ignition switch in the run position we noticed a buzzing it was the ignition relay. We change the relay and the replacement buzzed just the same. We also noticed the buzzing seemed to also coming from around the top of the engine. Upon further inspection we found out it was the ignition coils, now remember the engine is not running just the key is on. If we unplug the connectors to both coil packs the buzzing stops even the ignition relay. If you plug in either coil pack or both the buzzing returns. Pulling the spark plug wires and setting them up so they are all close to ground they all fire continuously nonstop all eight just like eight arc welders. We have load checked battery, pulled every ground apart and checked connections, the car is a low millage car that I don’t think has even seen rain.
Has anyone ever experienced the coils firing constantly, the car quits running then when checking for the problem with the ignition switch in the run position we noticed a buzzing it was the ignition relay. We change the relay and the replacement buzzed just the same. We also noticed the buzzing seemed to also coming from around the top of the engine. Upon further inspection we found out it was the ignition coils, now remember the engine is not running just the key is on. If we unplug the connectors to both coil packs the buzzing stops even the ignition relay. If you plug in either coil pack or both the buzzing returns. Pulling the spark plug wires and setting them up so they are all close to ground they all fire continuously nonstop all eight just like eight arc welders. We have load checked battery, pulled every ground apart and checked connections, the car is a low millage car that I don’t think has even seen rain.
