98 k1500 5.7L bucks and backfires??

1998 GMC SIERRA
130,000 MILES
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PETRUSOB
  • MEMBER
  • 1 POST
When you give it gas it bucks and backfires, take foot off pedal and idle runs good, as soon as you give it gas bucks backfires and sometime stalls but always starts up fine. What can it be??
Dec 26, 2011 at 4:15 AM
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RIVERMIKERAT
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  • 6,110 POSTS
Check the TPS and ignition timing. Also check compression. It could be a burned valve.
Dec 26, 2011 at 4:27 AM