HELP !! Burnt o2 extension causing misfire
Thread Starter
Racer
Joined: Oct 2010
Posts: 265
Likes: 1
From: MIAMI FL
HELP !! Burnt o2 extension causing misfire
Need some help guys.
The passenger side O2 extension plug fell onto my headers while I was driving causing a major misfire.
Brought the car back to my shop and put it on the lift. I noticed it was the plug. Changed it out and still misfire.
The whole passenger side coil pack is dead. The car starts but is running on 4 cylinders.
I check all the grounds. (Back of head bottom of block and starter side)
All the fuses are good too. The wire harness does not look to be burnt anywhere. I even swapped out the O2 sensors with other that I had and still the same problem.
I'm all out of options at this point.
I have searched and searched all leads to ground somewhere. But WHERE ?
I also notice when the car is on(misfiring) the MPH on the cluster is very dim when it's usually bright, leading to a ground. Right ?
Plugs/wires all new so I know it's not that.
Please any help is much appriciated. Thanks, Joe
The passenger side O2 extension plug fell onto my headers while I was driving causing a major misfire.
Brought the car back to my shop and put it on the lift. I noticed it was the plug. Changed it out and still misfire.
The whole passenger side coil pack is dead. The car starts but is running on 4 cylinders.
I check all the grounds. (Back of head bottom of block and starter side)
All the fuses are good too. The wire harness does not look to be burnt anywhere. I even swapped out the O2 sensors with other that I had and still the same problem.
I'm all out of options at this point.
I have searched and searched all leads to ground somewhere. But WHERE ?
I also notice when the car is on(misfiring) the MPH on the cluster is very dim when it's usually bright, leading to a ground. Right ?
Plugs/wires all new so I know it's not that.
Please any help is much appriciated. Thanks, Joe
Last edited by 99frccorvette; Mar 27, 2016 at 02:17 AM.
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, check for power at the coils... losing your front o2 sensor(s) will cause the car to run like crap but you shouldn't lose your coils, so something else is probably going on... I had a similar issue where I lost the passenger bank and it didn't take me long to find out why, no power at the coils and when I unplugged my extension harness this is what I found... after replacing the harness I haven't had an issue since, my only guess is maybe there was a loose terminal inside the connector causing it to get hot and melt
Thread Starter
Racer
Joined: Oct 2010
Posts: 265
Likes: 1
From: MIAMI FL
, check for power at the coils... losing your front o2 sensor(s) will cause the car to run like crap but you shouldn't lose your coils, so something else is probably going on... I had a similar issue where I lost the passenger bank and it didn't take me long to find out why, no power at the coils and when I unplugged my extension harness this is what I found... after replacing the harness I haven't had an issue since, my only guess is maybe there was a loose terminal inside the connector causing it to get hot and meltLast edited by 99frccorvette; Mar 27, 2016 at 12:28 PM.
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