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97 chevy 5.7l vortec. Backfired through intake and blew pcv valve line off the intake. Drove it 20 miles not knowing it was off, abnormally high idle. Reconnected line now i get a back and forth 3rd to 4th gear shift. Rpm amd speedo jump around when this happens. Rebuilt trans 6000 miles ago. Tested all solenoids in tranny, all good. No Cel no stored codes. Any ideas? Thanks
Hey Lee. Could be throttle position sensor issue (harness and/or wiring included). Throttle plate could have carbon buildup around it’s edges, as well. Also make sure vacuum lines and connections are sound. Hope this might help.
