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my car threw 14 engine codes!!! HELP

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Old Sep 4, 2013 | 10:24 PM
  #1  
Possum Boggs's Avatar
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Default my car threw 14 engine codes!!! HELP

i have a 99 z28 with longtubes and a small converter 3 in exhaust, i had it scanned at auto zone and it popped up all these codes below,also the egr is blocked off with a freeze plug and the smog pumps un hooked,the car hesitates and u can smell fuel,on code read a mis fire on cylinder 6,i changed the plugs and wires,checked for a bent pushrod and it was non of that, could it be a injector or coil making it mis fire? plzzz any info is appreciated!!!!!!!!!!!!!!

heres the codes it coded,A FEW WERE DUPLICATES THAT ADDED UP TO 14 CODES.....

P0135
P0140
P0160
P0300
P0405
P0465
P0140
P0306
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Old Sep 5, 2013 | 03:32 PM
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Duplicates mean some are pending and some are active, you really only have 7 codes.

P0135: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
P0140: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
P0160: O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2)
Did you forget to plug in your O2 sensors? Check for burnt O2 wires on the headers.

P0300: Random/Multiple Cylinder Misfire Detected
Could be related to the O2 sensor issue.

P0405: Exhaust Gas Recirculation Sensor A Circuit Low
You need to clear this code in the tune since you deleted EGR.

P0465: Purge Flow Sensor Circuit Malfunction
Did you do something to the EVAP?

P0306: Cylinder 6 Misfire Detected
Also could be related to the O2 sensor issue.

Fix the O2 sensor issue first. It may be causing the misfires. Also some people have low O2 activity issues with long tubes. Not sure what the cure is, but do a search.
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Old Sep 5, 2013 | 05:30 PM
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P0140: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
P0160: O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2)

If removed, the DTC is not turned off, and/or the "not reported" is not checked.
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Old Sep 5, 2013 | 10:49 PM
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ok thanks im going to try new 02's and see where that takes me
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Old Sep 7, 2013 | 01:26 AM
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www.gearchatter.com -> 1999 F-body DTC
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Old Sep 7, 2013 | 05:09 PM
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can the 02's bein bad make just a certain cylinder misfire? i was thinking a bad coil or injector possibly
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Old Sep 7, 2013 | 05:15 PM
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Originally Posted by Possum Boggs
can the 02's bein bad make just a certain cylinder misfire? i was thinking a bad coil or injector possibly
I was getting those same codes and it ended up being just a O2 so cheaper to replace one then going through everything else
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Old Sep 8, 2013 | 05:16 PM
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im thinking of gettn a set of 03 zo6 02's off ebay,i read that the corvettes had better 02's,is this a fix?
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Old Sep 9, 2013 | 01:07 AM
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Rear corvette LS1 O2s are a popular attempt to correct heating issues with long tubes, but not proven. I agree with checking all your O2 wiring. And make sure your rear O2s are tuned out.

If you suspect a coil issue, swap cyl 6 coil with another coil and see if the misfire moves
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