1986 GMC S15 popping back through carb

1986 GMC S15
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KICKINBACK47
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Engine Performance problem
1986 GMC S15 6 cyl Four Wheel Drive Manual

bought an older truck that was not running, replace a worn timing chain and gears which got the truck running again , also replaced the fuel pump, fuel filter, plugs, wires, cap,rotor, and control unit in the distributor, all of this made the truck run better but i am getting a poppin noise which sounds like it is comming from the carb. is there anything else i should try before i pull the heads or cam. after replacing the timming chain and gear the truck started the first time i tried it and idles fine but when you give it some gas the popping gets louder. any ideas ?
Apr 14, 2010 at 4:24 PM
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HMAC300
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a bent or broken pushrod will cause this as well as a burnt inlet vavle Or bent valve. take your valve covers off and check . If everything is ok then you'll have to check your compression and your lifters......
Apr 18, 2010 at 5:30 PM