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Help! LS1 sputtering/misfiring

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Old Feb 12, 2014 | 09:14 AM
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Default Help! LS1 sputtering/misfiring

So yesterday i went for a drive and it started to misfire when i would barely tap the gas to mantain the speed and i let go on the pedal and tap the pedal it would work fine and then it'll do it again. I went to my buddies shop and the scanner said that the o2 sensors are fucked. So i changed them last night and this morning i tried taking off and it was worse i had to put it back in the garage its running really rich now ever sinxe i put the o2 sensors...
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Old Feb 12, 2014 | 10:46 AM
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Data log it. Post it up. [Include the tune, too.]
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Old Feb 12, 2014 | 10:50 AM
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Nd it also backfired when i revved it a lil
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Old Feb 13, 2014 | 07:23 AM
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Bad O2 sensor codes can mean more than just the sensors are bad. Something could have cuased them to go bad which if unchecked will ruin the new ones too. A weak spark could foul the plugs.

I had really bad missfires once but only while on the throttle. Cruising around it was fine. The wires were bad. Weak spark.

Check your plugs. Are they covered in black? Wires and coils can be at fault as well.
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Old Feb 13, 2014 | 08:42 AM
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I actually scanned it again, i put the old o2 sensors on and it worked better but i got my Buddy's stock ls computer and connected it to my harness and everything was working great...so i guess i need to retune my computer where i got it done at..thanks!
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Old Feb 18, 2014 | 09:51 AM
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People say it acts funny cause i have open headers and the o2 sensors are an inch from the end of the headers...i keep it at 2-2500 rpms when its at a dead stop and it doesn't act weird but as soon as i go around 55mph at low rpm it acts dumb until i floor it. So Ima do the exhaust 1st and then see whats up
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Old Feb 18, 2014 | 10:00 AM
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You didn't mention you were running open headers. That could cetainly cause all of your issues.
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Old Feb 18, 2014 | 10:33 AM
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Yeah, I've heard that alot. I am going get the exhaust done today...
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Old Feb 18, 2014 | 10:33 AM
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Thanks
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Old Feb 18, 2014 | 03:18 PM
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Do you get the same issue as its warming up? Its only in closed loop (reading the O2's) after its reached a set temperature.
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Old Feb 19, 2014 | 09:34 AM
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Well it still kind of acts weird when I'm cruising... they told me to reset the computer so it can relearn itself...mean while that its quiet im gonna find all the air leaks and ticking haha
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Old Feb 19, 2014 | 09:35 AM
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Btw i welded some cats right after the headers and that's it....might just take off the cats and put like 4 foot of 3in piping after the headers dumped..
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