Cylinder 7 Misfire
Cylinder 7 Misfire Recently I have installed headers on my Camaro. I noticed at light throttle the car would sort of 'sputter' at light throttle, but the car was pretty quick at WOT, so I thought maybe that was just how the car ran. Well I put my scan gauge on the car tonight, and at idle, there is a light misfire on cylinder 7, and light to mid throttle there is a heavy misfire, but at WOT, the gauge read 0, so to the best of my ability, there is no misfire at WOT.
Anyway, I was wondering if you guys had any ideas on what it could be, I am going to start with the basics, wires, plugs, maybe switch coils, etc. I just wanted to see if there was anything I should know before I start messing around with this.
I was scanning with my aeroforce scan gauge. Also, I have stock coils, with MSD wires, and NGK TR6 plugs gapped at .050. I ran injector cleaner through the car about 2 months ago, so in theory everything should be good. Plugs have about 20 miles on them.
Thanks for any help.
Anyway, I was wondering if you guys had any ideas on what it could be, I am going to start with the basics, wires, plugs, maybe switch coils, etc. I just wanted to see if there was anything I should know before I start messing around with this.
I was scanning with my aeroforce scan gauge. Also, I have stock coils, with MSD wires, and NGK TR6 plugs gapped at .050. I ran injector cleaner through the car about 2 months ago, so in theory everything should be good. Plugs have about 20 miles on them.
Thanks for any help.
TECH Resident
Joined: Dec 2004
Posts: 845
Likes: 0
From: K-W, Ontario
Do a compression test on #7, and while you have the plug out take some
pics and post them.
If you've already swapped coil, plug and wire, I suspect something mechanical
like valve seating, or rings leaking.
pics and post them.
If you've already swapped coil, plug and wire, I suspect something mechanical
like valve seating, or rings leaking.
Recently I have installed headers on my Camaro. I noticed at light throttle the car would sort of 'sputter' at light throttle, but the car was pretty quick at WOT, so I thought maybe that was just how the car ran. Well I put my scan gauge on the car tonight, and at idle, there is a light misfire on cylinder 7, and light to mid throttle there is a heavy misfire, but at WOT, the gauge read 0, so to the best of my ability, there is no misfire at WOT.
Anyway, I was wondering if you guys had any ideas on what it could be, I am going to start with the basics, wires, plugs, maybe switch coils, etc. I just wanted to see if there was anything I should know before I start messing around with this.
I was scanning with my aeroforce scan gauge. Also, I have stock coils, with MSD wires, and NGK TR6 plugs gapped at .050. I ran injector cleaner through the car about 2 months ago, so in theory everything should be good. Plugs have about 20 miles on them.
Thanks for any help.
Anyway, I was wondering if you guys had any ideas on what it could be, I am going to start with the basics, wires, plugs, maybe switch coils, etc. I just wanted to see if there was anything I should know before I start messing around with this.
I was scanning with my aeroforce scan gauge. Also, I have stock coils, with MSD wires, and NGK TR6 plugs gapped at .050. I ran injector cleaner through the car about 2 months ago, so in theory everything should be good. Plugs have about 20 miles on them.
Thanks for any help.
I have not swapped anything yet. I am obviously going to start with the easy stuff first, swap the wire, swap the plug, then the coil, etc. Hopefully it is something easy lol.
FYI, my car has 51k miles on it, and it JUST recently started getting modded. The car was 100% stock up until 50k miles, hence why I can't see why it would be anything mechanical, but I guess I will rule that out if I can get rid of it electrically.
After doing a few different tests, the injectors were the next step. I took the fuel rail off, and pulled injector number 7 out, and a whole bunch of black sandy kind of stuff poured out onto my hand, so I looked in the injector and it was clogged as well. I then proceeded to pull all the injectors and clean the rail. Car runs like a champ now, thanks to all that helped.
