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Discussion Starter · #1 ·
Awhile ago I installed pacesetter LT headers and right after I had a misfire issue and replaced the sparks and wires, then my headers burned through the wires so I replaced those again and put heat sleeves over them, and tonight my truck started another misfire issue. as far as I could tell none of the wires are burned through. So my question is since all im running is LT headers and the Y-pipe is that burning my spark plugs up ? last time I took them out they were all burned up and they weren't very old.

I don't know too much about performance type things so lack of knowledge bashful comments and negative comments on running pretty much straight headers are expected but any input is appreciated and sorry for the novel and lack of pictures. :favorites37:
 

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I assume your truck isn't tuned at all? No handheld or anything? You have any other cels besides the one I assume you have now for the misfire? Have you checked the codes to see if it's one specific cylinder missing or multiple cylinders? Obviously the heat from the headers will burn the wires, and can still damage them internally with the heat shields. How close are they to the headers?
 

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Discussion Starter · #3 ·
Some wires are fine , and others were literally resting on the header ,
The only other codes I have are my rear o2 sensors cause they aren't plugged in , which would make it run lean? Or rich ? I forget the difference but could that be my problem ?

And I have no tune because I am waiting until I get my gears installed and I am getting it dyno/street tuned by a local LS dude,
 

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Discussion Starter · #4 ·
Also my fuel pump needs replaced , sometimes my truck will crank for a few seconds and not start and then second try starts immediately , recently hanged fuel filter battery and starter so that jut leaves fuel pump correct ? Not sure if my truck trying to start like that would have a correlation
 

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No rear 02 sensors will make it run rich, the computer stays in open loop and runs off a fixed air/fuel mixture which is on the rich side to protect the engine. Running rich can foul out your plugs and will turn them black with excess carbon.

As far as the hard start, it's possible it could be a weak fuel pump, but it's difficult to say without being able to check it while it doesn't start. Could be something simple as a bad coolant temp sensor for the ecu.

Swap a wire from a good cylinder to the bad one and see if that cures it. If so, get new wires. If not, switch a plug from a good cylinder to the bad one, if that fixes it, get new plugs. Either way, zip tie the wires up away from the headers.

I assume you unplugged the 02s because of the headers and removed cats? Are there holes in the exhaust for rear 02s? If so, I'd just plug them back in for now. If you put a spark plug de fouler on the 02 sensor before you put it in the exhaust, it may trick the computer into thinking there's a cat also.
 

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Also my fuel pump needs replaced , sometimes my truck will crank for a few seconds and not start and then second try starts immediately , recently hanged fuel filter battery and starter so that jut leaves fuel pump correct ? Not sure if my truck trying to start like that would have a correlation
If you really have straight pipes with headers, you need a tune bad.

No rear 02 sensors will make it run rich, the computer stays in open loop and runs off a fixed air/fuel mixture which is on the rich side to protect the engine. Running rich can foul out your plugs and will turn them black with excess carbon.

As far as the hard start, it's possible it could be a weak fuel pump, but it's difficult to say without being able to check it while it doesn't start. Could be something simple as a bad coolant temp sensor for the ecu.

Swap a wire from a good cylinder to the bad one and see if that cures it. If so, get new wires. If not, switch a plug from a good cylinder to the bad one, if that fixes it, get new plugs. Either way, zip tie the wires up away from the headers.

I assume you unplugged the 02s because of the headers and removed cats? Are there holes in the exhaust for rear 02s? If so, I'd just plug them back in for now. If you put a spark plug de fouler on the 02 sensor before you put it in the exhaust, it may trick the computer into thinking there's a cat also.
Rear O2 sensors have nothing at all to do with Air/Fuel mixture. Front O2's take care of that.
 

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Rear O2 sensors have nothing at all to do with Air/Fuel mixture. Front O2's take care of that.
but the rear o2 is looking for the cat...it sees none, trips code n ecm runs rich
 

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Discussion Starter · #10 ·
yeah I don't even have spots for rear 02s cause I have no more exhaust past the y pipe, haven't gotten to it yet only spots for the front. I just want to delete them with a tune,
I do need a tune bad and im workin on it haha
BE115396-2683-4F1E-A244-FB7A7C675038.jpg
but I found this and since I have to go to work today I didn't wanna pull all the plugs, but replaced the wires and no misfire now, but I still wanna check out my spark plugs sometime this weekend
 

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Discussion Starter · #11 ·
but the rear o2 is looking for the cat...it sees none, trips code n ecm runs rich
is there a difference of having them unplugged and still connected and not in the exhaust ?
 

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your plugs are probably fine...you gotta fix the plug burning issue though. I had no problems with plug burning on my NBS with pacesetters. One thing u can do is to turn the angled boot at the coil to try and pull the wire away from the primary. If that wont work, you might want to use header wrap at the contact points and secure it with clamps or safety wire.
 

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is there a difference of having them unplugged and still connected and not in the exhaust ?
idk, but id just disconnect them just in case
 

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Discussion Starter · #14 ·
alright ive had them disconnected the whole time, truck runs really weird right after the battery is disconnected and everything is reset or whatever but that's just gotta be the lack of tune,

I bought these headers off my friends 05 sierra 5.3 and he had none of these burning issues ,

I think ill pick up some wrap
 

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get a tune and have the rears deleated.... the frount is for yout Air/Fuel mix and the rears are for emissions. without propper tuning the rears and even the fronts wont read correctly within the factory peramotors. gotta remember the computer tho will however adjust the short term fuel trims but it my not be enough... just saying.
 

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alright ive had them disconnected the whole time, truck runs really weird right after the battery is disconnected and everything is reset or whatever but that's just gotta be the lack of tune,

I bought these headers off my friends 05 sierra 5.3 and he had none of these burning issues ,

I think ill pick up some wrap
Youre probably running aftermarket wires and are longer or he had shorter wires. If you go toany autoparts store...ask for camaro or gto wires..I THINK those are a bit shorter....try them out on your truck.

Your truck will run funny after battery disconnect because its learning how to idle again....itll want to die qhen u come to a stop or just at idle.
 

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Discussion Starter · #17 ·
yeah that's exactly what it would do, but it relearns

and ill look into some shorter wires next time, replacing the wires isn't too much of a big deal cause they are warrantied and it doesn't cost me anything but a little time a pain in my ass

thanks for the help dudes appreciate it
 

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i was running my msd's with mine and i got plug boots and used bailing wire to hold them outa the way... never had a issue for 2 years.
 

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yeah I don't even have spots for rear 02s cause I have no more exhaust past the y pipe, haven't gotten to it yet only spots for the front. I just want to delete them with a tune,
I do need a tune bad and im workin on it haha
BE115396-2683-4F1E-A244-FB7A7C675038.jpg
but I found this and since I have to go to work today I didn't wanna pull all the plugs, but replaced the wires and no misfire now, but I still wanna check out my spark plugs sometime this weekend
Damn, that'd cause lightning at night
 

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Discussion Starter · #20 ·
There was a spark wire heat wrap sleeve over it so I didn't see the light lol , but I have seen what your talk about before , looks crazy
 
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