Why is my truck backfiring?
I got a new break booster and put it on, then replaced the transmission filter. Ever since
I've done this, this extremely loud backfire comes from the left exhaust pipe. I don't know
what's going on with it
Check if you have an A.I.R. system (smog pump). If so, you may have accidentally disconnected the vacuum hose from the diverter valve. I'd strongly suspect this if it only backfires when you take your foot off the gas pedal. HTH. -Jim
Check your plug wires or spark plugs on that side. You may have pulled one off or cracked the porcelain on the spark plug installing the booster.
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