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After Headers, Runs Like Crap

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Old Aug 7, 2014 | 05:57 PM
  #1  
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Default After Headers, Runs Like Crap

Hey all,

Just some starting info:
02 Camaro z28
AIR removed
LT Headers
ORY
NO rear o2's (not tuned out just not pluged in)
Stock Everything Else

I just recently put LT's on, and while i had it apart, changed plugs & wires.
Took the car out for the first time, and it runs like crap.

It hesitates, surges, bogs, etc. Ran great before all this.

Had no issues prior.

Here's what im thinking, i am guessing bad o2. and would like to know what readings i should be getting.
When I run my scan tool, i can view current data and see o2 voltages. The data is as follows at just idle, no throttle change:
o2s11 .1-1
o2s12 .445 steady (bc its not plugged in???)
o2s21 .445 steady
o2s22 .445 steady (bc its not plugged in???)

so im wondering, at idle, is the correct reading the one that changes or the one that is steady? I would guess the one that moves, which would indicate it is trying to adjust for AFR. but im not sure.

I also am getting codes for a random misfire p0300

Looking to get my car back to being responsive and running well again.

Thanks in advance for any help.
Grady
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Old Aug 8, 2014 | 07:27 AM
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Your 02's are not working.
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Old Aug 8, 2014 | 07:47 AM
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Upstream sensors are supposed to be switching. The one upstream sensor that is a steady voltage reading is not working.
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Old Aug 13, 2014 | 06:22 AM
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Check that you didn't crack any spark plugs when you installed the headers.

Also check that you didn't damage the ECT sensor (located at the front of the LHS head).
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