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lq4 spark knock/missfire at idle

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Old Apr 14, 2015 | 06:40 PM
  #21  
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would a possibility of the tune be the reason its pulling timing? it has a 87 black bear tune but i never got a crank relearn. only because it never had an check engine light. it still had a rough/missfirey idle before the tune.
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Old Apr 14, 2015 | 07:46 PM
  #22  
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If the problem was occurring before the tune then it sounds like it wasnt tune related. Although it wouldnt hurt to swap the stock pcm back in and see if its better or worse.
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Old Apr 14, 2015 | 08:02 PM
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no the shitty idle was there from when i bough it a couples months ago bone stock. i changed the knock sensors bc of the cel, i also watched the live data before i changed my sensors /pcm and it never pulled timing. i changed the sensors and the pcm at the same time and thats where im at now. the whole idle thing is unrelated to the tune, the knock retard is, i think
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Old Apr 15, 2015 | 08:59 PM
  #24  
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This is kinda tricky..... Did you replace the intake gaskets when you changed the knock sensors?
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Old Apr 17, 2015 | 09:50 PM
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yes fel pro
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Old Apr 18, 2015 | 05:40 PM
  #26  
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Well I switch my stock pcm and tune in and it still pulls timing at wot. Has new knock sensors but I think it's from the wrong torque on them. That could be possibly setting it off. Is this causing any damage or loss of power?
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Old Apr 19, 2015 | 08:04 AM
  #27  
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Yes any time the pcm is pulling timing your losing power. The torque is critical for the knock sensors.
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Old Apr 19, 2015 | 08:11 AM
  #28  
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so it looks like im pulling the intake again and re torquing them?
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Old Apr 19, 2015 | 09:58 AM
  #29  
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is it causing any damage?
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Old Apr 21, 2015 | 11:38 AM
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Since you have tried many other things it would be nice to go back and retorque your knock sensors just so you can rule out any possible problems from that. IMHO, i dont feel like you would be getting misfiring from improperly torqued knock sensors.
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