Spark, spark, spark everywhere
Thread Starter
Racer
Joined: Aug 2002
Posts: 369
Likes: 11
From: NV
Spark, spark, spark everywhere
So......the saga of my gremlins continues.
Developed a misfire after putting in new plugs. I checked gaps on each. I DID NOT change plug wires, and actually had one separate from the connector when I was pulling them off (Granatelli 8mm with covers). I repaired it and reused the wires. After buttoning everything up I had a misfire. DTC O315 (I think)... It was a coil misfire secondary circuit.
So I started pulling one wire at a time with engine running. The first one caused the engine to run worse (obviously not the bad coil/wire) but I began to see sparks all over the area of the valve cover, here, there, everywhere! Seemingly following the coil bracket. I thought that was quite strange, shut it down, reattached wire. Sparks gone. I wanted to check the wire that I had repaired and when I did I got no spark. You would think that suggested the wire was bad or not repaired successfully but the coil was not showing any spark, seemed dead. So thats where I am....I plan on new wires......any suggestions on definitively testing the coil/s? Should I replace all or just the malfunctioning coil? Review of forum posts suggest staying with GM OEM...so that part is easy. What say my fellow enthusiasts?
Developed a misfire after putting in new plugs. I checked gaps on each. I DID NOT change plug wires, and actually had one separate from the connector when I was pulling them off (Granatelli 8mm with covers). I repaired it and reused the wires. After buttoning everything up I had a misfire. DTC O315 (I think)... It was a coil misfire secondary circuit.
So I started pulling one wire at a time with engine running. The first one caused the engine to run worse (obviously not the bad coil/wire) but I began to see sparks all over the area of the valve cover, here, there, everywhere! Seemingly following the coil bracket. I thought that was quite strange, shut it down, reattached wire. Sparks gone. I wanted to check the wire that I had repaired and when I did I got no spark. You would think that suggested the wire was bad or not repaired successfully but the coil was not showing any spark, seemed dead. So thats where I am....I plan on new wires......any suggestions on definitively testing the coil/s? Should I replace all or just the malfunctioning coil? Review of forum posts suggest staying with GM OEM...so that part is easy. What say my fellow enthusiasts?
Safety Car
Joined: Nov 2002
Posts: 4,394
Likes: 6
From: Melbourne FL
replace all the plug wires first. Then see if you still have no spark at that coil. Then check the coil wiring. If all looks good; swap the bad coil for one of your good coils and see if you have spark at that spot. If so, replace bad coil. It would be unusual for a coil to go bad during a plug swap.
Tech Contributor
Joined: Jan 2007
Posts: 19,450
Likes: 1,155
From: Dyer, IN
So......the saga of my gremlins continues.
Developed a misfire after putting in new plugs. I checked gaps on each. I DID NOT change plug wires, and actually had one separate from the connector when I was pulling them off (Granatelli 8mm with covers). I repaired it and reused the wires. After buttoning everything up I had a misfire. DTC O315 (I think)... It was a coil misfire secondary circuit.
So I started pulling one wire at a time with engine running. The first one caused the engine to run worse (obviously not the bad coil/wire) but I began to see sparks all over the area of the valve cover, here, there, everywhere! Seemingly following the coil bracket. I thought that was quite strange, shut it down, reattached wire. Sparks gone. I wanted to check the wire that I had repaired and when I did I got no spark. You would think that suggested the wire was bad or not repaired successfully but the coil was not showing any spark, seemed dead. So thats where I am....I plan on new wires......any suggestions on definitively testing the coil/s? Should I replace all or just the malfunctioning coil? Review of forum posts suggest staying with GM OEM...so that part is easy. What say my fellow enthusiasts?
Developed a misfire after putting in new plugs. I checked gaps on each. I DID NOT change plug wires, and actually had one separate from the connector when I was pulling them off (Granatelli 8mm with covers). I repaired it and reused the wires. After buttoning everything up I had a misfire. DTC O315 (I think)... It was a coil misfire secondary circuit.
So I started pulling one wire at a time with engine running. The first one caused the engine to run worse (obviously not the bad coil/wire) but I began to see sparks all over the area of the valve cover, here, there, everywhere! Seemingly following the coil bracket. I thought that was quite strange, shut it down, reattached wire. Sparks gone. I wanted to check the wire that I had repaired and when I did I got no spark. You would think that suggested the wire was bad or not repaired successfully but the coil was not showing any spark, seemed dead. So thats where I am....I plan on new wires......any suggestions on definitively testing the coil/s? Should I replace all or just the malfunctioning coil? Review of forum posts suggest staying with GM OEM...so that part is easy. What say my fellow enthusiasts?
