LG Pro Longtubes Installed - Multiple Misfires
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
LG Pro Longtubes Installed - Multiple Misfires
I had a local shop install the LG Pro Longtube system on my 2001 Z06. I went to pick it up today, and it had multiple misfires and was running extremely rough. I left it at the shop to get it tuned (was going to wait) and get the issues resolved.
During the installation and removal of the spark plug wires, one of them was broken. They had plug wires from an LS series car on hand and substituted one from the kit. The car did the same thing, multiple misfires and very rough running. He then swapped all of the plug wires with new ones. Again, same issues.
I left the car there and they will be checking out the spark plugs and getting the car tuned on the dyno. I am confident that the shop will get the problems resolved, but since I won't be picking the car up till Friday due to my own busy schedule...I'm kind of curious.
Has anyone experienced this same thing?
What could be the problem?
Can any damage result from a misfire condition?
Thanks!
During the installation and removal of the spark plug wires, one of them was broken. They had plug wires from an LS series car on hand and substituted one from the kit. The car did the same thing, multiple misfires and very rough running. He then swapped all of the plug wires with new ones. Again, same issues.
I left the car there and they will be checking out the spark plugs and getting the car tuned on the dyno. I am confident that the shop will get the problems resolved, but since I won't be picking the car up till Friday due to my own busy schedule...I'm kind of curious.
Has anyone experienced this same thing?
What could be the problem?
Can any damage result from a misfire condition?
Thanks!
Last edited by Quickshift_C5; Aug 26, 2009 at 12:02 AM.
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
I had a local shop install the LG Pro Longtube system on my 2001 Z06. I went to pick it up today, and it had multiple misfires and was running extremely rough. I left it at the shop to get it tuned (was going to wait) and get the issues resolved.
During the installation and removal of the spark plug wires, one of them was broken. They had plug wires from an LS series car on hand and substituted one from the kit. The car did the same thing, multiple misfires and very rough running. He then swapped all of the plug wires with new ones. Again, same issues.
I left the car there and they will be checking out the spark plugs and getting the car tuned on the dyno. I am confident that the shop will get the problems resolved, but since I won't be picking the car up till Friday due to my own busy schedule...I'm kind of curious.
Has anyone experienced this same thing?
What could be the problem?
Can any damage result from a misfire condition?
Thanks!
During the installation and removal of the spark plug wires, one of them was broken. They had plug wires from an LS series car on hand and substituted one from the kit. The car did the same thing, multiple misfires and very rough running. He then swapped all of the plug wires with new ones. Again, same issues.
I left the car there and they will be checking out the spark plugs and getting the car tuned on the dyno. I am confident that the shop will get the problems resolved, but since I won't be picking the car up till Friday due to my own busy schedule...I'm kind of curious.
Has anyone experienced this same thing?
What could be the problem?
Can any damage result from a misfire condition?
Thanks!
Safety Car
Joined: May 2004
Posts: 4,811
Likes: 2
From: Simpsonville SC
One of the plugs could be broken, when they put them back in they could of tightened them to tight or if they didnt take them out the plugs could of got hit and broke. Other than not seeing the car in person, theres no tellin. I hope they find it and its something simple. Good Luck with it
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
Thanks!
I'm going to talk to the shop owner in the morning and talk with him about it a bit. I may just have them replace the plugs anyway. The car has 28k miles and it has the original plugs/wires. Well, it had the original wires.
Let's talk about the 02 sensor wires. There was a problem during installation where the wires that I recieved with the setup (bought secondhand) wouldn't work. They did some research and found out that those 02 sensor extensions were actually for a C6. The person who sent them to me sent the wrong ones with the longtubes. It was a simple fix, as they just took it apart, extended it, and repinned it. Car was installed with no cats, if that info is necessary.
So with that in mind, this could be a valid discussion point. I assume it could be possible that it may have been pinned wrong or they may have crossed the wires during install? Crossing the 02 sensors will cause it to misfire? I don't see how the 02 sensors are related to a misfire condition, wouldn't it just throw the check engine light due to a smog error?
I'm going to talk to the shop owner in the morning and talk with him about it a bit. I may just have them replace the plugs anyway. The car has 28k miles and it has the original plugs/wires. Well, it had the original wires.
Let's talk about the 02 sensor wires. There was a problem during installation where the wires that I recieved with the setup (bought secondhand) wouldn't work. They did some research and found out that those 02 sensor extensions were actually for a C6. The person who sent them to me sent the wrong ones with the longtubes. It was a simple fix, as they just took it apart, extended it, and repinned it. Car was installed with no cats, if that info is necessary.
So with that in mind, this could be a valid discussion point. I assume it could be possible that it may have been pinned wrong or they may have crossed the wires during install? Crossing the 02 sensors will cause it to misfire? I don't see how the 02 sensors are related to a misfire condition, wouldn't it just throw the check engine light due to a smog error?
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
Thanks!
I'm going to talk to the shop owner in the morning and talk with him about it a bit. I may just have them replace the plugs anyway. The car has 28k miles and it has the original plugs/wires. Well, it had the original wires.
Let's talk about the 02 sensor wires. There was a problem during installation where the wires that I recieved with the setup (bought secondhand) wouldn't work. They did some research and found out that those 02 sensor extensions were actually for a C6. The person who sent them to me sent the wrong ones with the longtubes. It was a simple fix, as they just took it apart, extended it, and repinned it. Car was installed with no cats, if that info is necessary.
So with that in mind, this could be a valid discussion point. I assume it could be possible that it may have been pinned wrong or they may have crossed the wires during install? Crossing the 02 sensors will cause it to misfire? I don't see how the 02 sensors are related to a misfire condition, wouldn't it just throw the check engine light due to a smog error?
I'm going to talk to the shop owner in the morning and talk with him about it a bit. I may just have them replace the plugs anyway. The car has 28k miles and it has the original plugs/wires. Well, it had the original wires.
Let's talk about the 02 sensor wires. There was a problem during installation where the wires that I recieved with the setup (bought secondhand) wouldn't work. They did some research and found out that those 02 sensor extensions were actually for a C6. The person who sent them to me sent the wrong ones with the longtubes. It was a simple fix, as they just took it apart, extended it, and repinned it. Car was installed with no cats, if that info is necessary.
So with that in mind, this could be a valid discussion point. I assume it could be possible that it may have been pinned wrong or they may have crossed the wires during install? Crossing the 02 sensors will cause it to misfire? I don't see how the 02 sensors are related to a misfire condition, wouldn't it just throw the check engine light due to a smog error?
I'm working late from my home office. I'll PM you my number if you want to discuss.
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
I'm working late from my home office. I'll PM you my number if you want to discuss.
Thanks guys!
Going to have the shop swap out all of the plugs and then look at the wiring for the 02 sensors. Can't wait to get the car back. It sounded absolutely amazing the short time I had it.
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Safety Car
Joined: Jul 2001
Posts: 4,661
Likes: 67
From: Ocean Springs MS
The computer uses the O2 readings to adjust fuel trims. If it's trying to adjust fuel on the one side while using readings from the other side due to crossed wires, your car will run like crap. It's a well documented mistake during C5 header installs.
Pro
Joined: Jan 2008
Posts: 740
Likes: 3
From: Temecula California
Im a lil perplexed, I did my own install with long tubes and was given the wrong o2 extensions, I drove the car for a week with NO o2s hooked up at, front or rear, no cats mind you but other than a check engine light for obvious reasons, the car ran pretty good. Only real obvious difference was the mileage went way down as I expected it to.
So Im thinkin like some others here that your problem would lie with the plugs or wires or both?? not sure O2s will make misfires, I guess they could if you drove around for a while and maybe fouled a plug?
jus my .02 no pun intended lol
So Im thinkin like some others here that your problem would lie with the plugs or wires or both?? not sure O2s will make misfires, I guess they could if you drove around for a while and maybe fouled a plug?
jus my .02 no pun intended lol
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
The guys at the shop explained to me that this was one of the tests they did to determing if the 02 wiring was bad. It ran with mulitple misfires with 02 wiring connected. They ran it with 02 wiring disconnected and it ran ok. It ran "OK", but they explained to me that it retards timing substantially and the computer does a number of things to degrade performance/power and run safe. I couldn't give you the details since I'm obviously not the pro on this, but that's how it was explained to me.
From what I understand, with all the 02 wiring disconnected the computer goes into "limp mode" just to get the vehicle in running condition to get you home. It's by no means running great, but it will run. That's how they explained it to me anyway...
From what I understand, with all the 02 wiring disconnected the computer goes into "limp mode" just to get the vehicle in running condition to get you home. It's by no means running great, but it will run. That's how they explained it to me anyway...
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
The guys at the shop explained to me that this was one of the tests they did to determing if the 02 wiring was bad. It ran with mulitple misfires with 02 wiring connected. They ran it with 02 wiring disconnected and it ran ok. It ran "OK", but they explained to me that it retards timing substantially and the computer does a number of things to degrade performance/power and run safe. I couldn't give you the details since I'm obviously not the pro on this, but that's how it was explained to me.
From what I understand, with all the 02 wiring disconnected the computer goes into "limp mode" just to get the vehicle in running condition to get you home. It's by no means running great, but it will run. That's how they explained it to me anyway...
From what I understand, with all the 02 wiring disconnected the computer goes into "limp mode" just to get the vehicle in running condition to get you home. It's by no means running great, but it will run. That's how they explained it to me anyway...
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
1) What exactly did they re-pin?
2) Why didn't they use the LG adapters?
3) Have the plugs been inspected/changed?
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
Would love to know the answer myself, I am still waiting on the call from them on the status of the car.
Is what I said above true or false, just curious if there is any accuracy in it at all.
Tech Contributor
Joined: Jan 2007
Posts: 19,470
Likes: 1,171
From: Dyer, IN
Honestly, I've never heard of that type of troubleshooting to find a bad O2(or associated wiring) before. The service manual, schematics, and tuning software is all they need to isolate wiring/sensor issues. How they can assess the motor's behavior, with respect to the O2 sensors(front) by leaving them disconnected(while running in a closed loop) is beyond me. Like I said on the phone, I question if these guys know what the heck they are doing.....
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
Honestly, I've never heard of that type of troubleshooting to find a bad O2(or associated wiring) before. The service manual, schematics, and tuning software is all they need to isolate wiring/sensor issues. How they can assess the motor's behavior, with respect to the O2 sensors(front) by leaving them disconnected(while running in a closed loop) is beyond me. Like I said on the phone, I question if these guys know what the heck they are doing.....
Just waiting to see what happens at this point. Not sure what else I can do on my end.
