Misfire after header install? Help please!
Thread Starter
3rd Gear
Joined: Feb 2017
Posts: 3
Likes: 0
Misfire after header install? Help please!
Hey all, first post on the forum
I own a 2002 z06 with 27,000 miles, just got done putting in LG Super Pro 1 3/4 headers with a catless x-pipe, through the stock Ti system with the bypass mod.
At first startup everything seemed good, no air leaks, sounded awesome
and I was very happy with the results, now once the car was let to warm up to operating temp (200-220) check engine light came on P0306 (cylinder 6 misfire) and I have no clue where to start because the obvious has already been checked, switched plugs, wires, coil pack, so the question is, do i just need a tune or do i have more issues at hand? Would appreciate any feedback that would be helpful and if anybody is curious on the Ti Mod, I have all the information needed for anybody wanting to do it. Thanks!
I own a 2002 z06 with 27,000 miles, just got done putting in LG Super Pro 1 3/4 headers with a catless x-pipe, through the stock Ti system with the bypass mod.
At first startup everything seemed good, no air leaks, sounded awesome
and I was very happy with the results, now once the car was let to warm up to operating temp (200-220) check engine light came on P0306 (cylinder 6 misfire) and I have no clue where to start because the obvious has already been checked, switched plugs, wires, coil pack, so the question is, do i just need a tune or do i have more issues at hand? Would appreciate any feedback that would be helpful and if anybody is curious on the Ti Mod, I have all the information needed for anybody wanting to do it. Thanks!
Safety Car
Joined: Feb 2013
Posts: 4,346
Likes: 755
From: Greensboro Nc
Very unlikely that it's just a tune issue. Do you have a specific cylinder that it's throwing a misfire code for?
I have seen many cracked plugs during header installs, as well as the obvious potential for the wires to be shorting on the primary. When you checked plugs/wires did you replace all of them? I had a cylinder 2 misfire, changed wire/swapped coil/swapped injectors to no avail. Turned out it was the wire on the cylinder right ahead of cylinder two that was shorting and somehow making cylinder 2 throw the code. 8 new wires and it was perfect.
I have seen many cracked plugs during header installs, as well as the obvious potential for the wires to be shorting on the primary. When you checked plugs/wires did you replace all of them? I had a cylinder 2 misfire, changed wire/swapped coil/swapped injectors to no avail. Turned out it was the wire on the cylinder right ahead of cylinder two that was shorting and somehow making cylinder 2 throw the code. 8 new wires and it was perfect.
Thread Starter
3rd Gear
Joined: Feb 2017
Posts: 3
Likes: 0
Very unlikely that it's just a tune issue. Do you have a specific cylinder that it's throwing a misfire code for?
I have seen many cracked plugs during header installs, as well as the obvious potential for the wires to be shorting on the primary. When you checked plugs/wires did you replace all of them? I had a cylinder 2 misfire, changed wire/swapped coil/swapped injectors to no avail. Turned out it was the wire on the cylinder right ahead of cylinder two that was shorting and somehow making cylinder 2 throw the code. 8 new wires and it was perfect.
I have seen many cracked plugs during header installs, as well as the obvious potential for the wires to be shorting on the primary. When you checked plugs/wires did you replace all of them? I had a cylinder 2 misfire, changed wire/swapped coil/swapped injectors to no avail. Turned out it was the wire on the cylinder right ahead of cylinder two that was shorting and somehow making cylinder 2 throw the code. 8 new wires and it was perfect.
Burning Brakes
Joined: May 2013
Posts: 1,249
Likes: 142
From: Lynn MA
I had the same issue after header install. And it was that the plug wire had heated up dried and cracked. I would take that wire completely off and inspect it closely while moving and bending it. JMO
Team Owner
Joined: May 2001
Posts: 87,375
Likes: 1,593
From: Western NY
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Thread Starter
3rd Gear
Joined: Feb 2017
Posts: 3
Likes: 0
Fixed!!!
Hello everyone, the problem is fixed and the vette is back to running like a top.
I had to move the 02 sensors up to the fitting in the header, and then rewire then to drivers side header went to drivers side connection, and passenger side header went to passenger side connection, just figured I would give this tip out as the instructions for wiring are somewhat confusing as to where they go.
So in summary the "misfire" was probably a combination of running STUPID rich, along with the PCM not knowing what was going on, appreciate the input from everyone!
-LG Super Pro 1 3/4" & O/R X Pipe
I had to move the 02 sensors up to the fitting in the header, and then rewire then to drivers side header went to drivers side connection, and passenger side header went to passenger side connection, just figured I would give this tip out as the instructions for wiring are somewhat confusing as to where they go.
So in summary the "misfire" was probably a combination of running STUPID rich, along with the PCM not knowing what was going on, appreciate the input from everyone!
-LG Super Pro 1 3/4" & O/R X Pipe
Racer
Joined: May 2009
Posts: 298
Likes: 9
From: Prince Frederick Southern Maryland
Hello everyone, the problem is fixed and the vette is back to running like a top.
I had to move the 02 sensors up to the fitting in the header, and then rewire then to drivers side header went to drivers side connection, and passenger side header went to passenger side connection, just figured I would give this tip out as the instructions for wiring are somewhat confusing as to where they go.
So in summary the "misfire" was probably a combination of running STUPID rich, along with the PCM not knowing what was going on, appreciate the input from everyone!
-LG Super Pro 1 3/4" & O/R X Pipe
I had to move the 02 sensors up to the fitting in the header, and then rewire then to drivers side header went to drivers side connection, and passenger side header went to passenger side connection, just figured I would give this tip out as the instructions for wiring are somewhat confusing as to where they go.
So in summary the "misfire" was probably a combination of running STUPID rich, along with the PCM not knowing what was going on, appreciate the input from everyone!
-LG Super Pro 1 3/4" & O/R X Pipe
