Q: P0300 code random misfire code

asked by on November 02, 2016

My 1999 GMC Yukon slt has been having this P0300 random misfire code come on but it come on and go off every week and when it does its hard to start my truck I have to hit the gas to get it started

Hi. Several components could cause this problem - old, failing plug wires, old plugs with wide gaps, worn or corroded distributor cap or rotor contacts, failing distributor pickup coil issues, or failing ignition coil packs. Diagnosis with proper electrical testing gear is the only way to isolate random misfire issues. For further help, a certified professional from YourMechanic, can come to your car’s location to inspect the misfiring issue and move forward with repairs.

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