knock sensor retarding timing

PONTIAC GRAND PRIX
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WILL GIBSON
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  • 3 POSTS
My '96 Pontiac Grand Prix with 147K on 3.1 V6's knock sensor has taken to retard the timing to 0 and less. It only does it after it has been driven for about 15 minutes or so. Then, as you excellerate up to say 50, at about 2,000 rpm it quits excellerating, untill it finally downshifts, and then it runs great. Once you level off, if you try to accelerate, nothing happens untill it downshifts again. Once it gets over 3,000 rpm, it'll run fine. But who can cruise at 100?
Feb 15, 2007 at 2:39 PM
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2CARPRO JACK
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Any check engine light? If so lets get it scanned and go from there
Feb 16, 2007 at 7:49 AM
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WILL GIBSON
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  • 3 POSTS
No check engine or SES ever came on.
Feb 16, 2007 at 1:36 PM
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WILL GIBSON
  • MEMBER
  • 3 POSTS
Scan was uneventfull untill under a light load at 2K, and then the timing started retarding to zero if you kept your foot in in.
Feb 16, 2007 at 1:38 PM
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