i have changed everything........

hi i need serious help.my truck is missing and backfiring when at lower
speeds but runs better at higher speeds.i have a 1994 b2300.i have changed spark plugs and plug wires,brand new o2 sensor,new brakes and brake calipers on front and it still runs bad. what to do?????any help would be appreciated. thank you.

Whats the idle at?, if you don't have a Tach you can buy an inexpensive one at a autoparts store. Then check with truck in drive against sticker on inside of hood.

you may want to check the timeing on your truck.

I have a 90 mazda b2600i 2wd and Im basically having the same problem except for the backfiring. I changed plugs,wires,cap,rotor,and fuel filter. The problem with mine is whenever its moist,or raining out,it misses like hell untill i get up to around 55mph,then it will go away. I thought maybe i burned a plug,but I checked them and there fine. I even put silicone around the cap to make sure theres no moisture getting into the cap.Any help would be appreciated. I just dont know what else to do.

I have a 1993 2600i and when i first got it, it would do the same thing, studder, and feel likes it missing, but then i installed venom injectors, and a ractive intake, and i haven't had a problem since. :cheers:

I have a 90 mazda b2600i 2wd and Im basically having the same problem except for the backfiring. I changed plugs,wires,cap,rotor,and fuel filter. The problem with mine is whenever its moist,or raining out,it misses like hell untill i get up to around 55mph,then it will go away. I thought maybe i burned a plug,but I checked them and there fine. I even put silicone around the cap to make sure theres no moisture getting into the cap.Any help would be appreciated. I just dont know what else to do.

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