3.4 L 95 Firebird bucking and backfiring at certain speeds and seatbelft light stays on

Sorry for all the bandwidth but here we going again
Engine: 3.4L 1995 Bird Problem Description: Engine 'bucking' and some backfiring at 45, 55, and 65 MPH.
Driver Observations that might be useful: Seams to happen more on hills or when Passengers are in car vs. driving alone. Most often at 55 MPH.
Problem Two
Seat belt light stays on always????? Yes the seatbelt is buckled :)
Thanks.
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Jay Barboza wrote:

You can google our previous responses.
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Go to www.alldata.com and look for any bulletins or recalls that pertain to these problems.
If you find any, go to any GM dealer with the # and they can print out the bulletin for you. Then you'll know the fix.
Start there first. Joe--ASE Certified Parts Specialist & 10th Ann.Club Tech Director '80 Carousel Red Turbo T/A, 26k orig. '79 "Y89" 400/4 speed 10th Ann. T/A, 57k orig '84 Olds 88 Royale Bgm 2 dr, 307 "Rocket" (lol), 141k and still going.... '80 T/A project car...
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the back firing problem might be a bad cadillac converter, mine did that when i changed out the muffler then i quickley replaced it and it sounds alot better..... backfiring sounds so bad
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I didn't know "Cadillac" made converters. LOL :)
You mean "catalytic". And if the converter IS stuffed, something is causing that and must be found, or the new one will get stuffed again in short order :).
Joe--ASE Certified Parts Specialist & 10th Ann.Club Tech Director '80 Carousel Red Turbo T/A, 26k orig. '79 "Y89" 400/4 speed 10th Ann. T/A, 57k orig '84 Olds 88 Royale Bgm 2 dr, 307 "Rocket" (lol), 141k and still going.... '80 T/A project car...
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