1998 Buick LeSabre P0300

Fault code P0300. Random misfire detected. Never had this problem. 95,000 miles. need some help.

3800 V6 engine, coil packs need replacing, most likely. Change the spark plugs and wires first to see if it goes away.

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Thank you very much for responding.

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Don’t replace the coil packs.

If there were a bad coil pack it would cause a major misfire code.

Just replace the plugs and wires.

Tester

Before you replace plugs and coil packs, Check for a cracked plug wire. Maybe rubbing on something causing an intermittent arc.
Spray some water on the ignition while the motor is running. That should show you where the fault is.
Mustangman , I agree.

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I will check this out Thanks.

_i HAD THE SAME PROBLEM SO THE FIRST THING i DID IS CHECK WITH A CODER WHICH CYLINDER WAS MISFIRING THEN WENT TO THAT COIL REMOVED THE WIRE AND CLEANED ALL AROUND THE COIL TOWER AND COIL ITSELF WITH A LITTLE BRUSH AND SOME RUBBING ALCOHOL
THEN CLEANED THE WIRE WITH A RAG AND ALCOHOL AND PULLED THE WIRE OFF THE SPARK PLUG CLEANED THE PLUG END AND THE INSIDE OF THE BOOT WITH A CU-TIP AND SOME ALCOHOL. THEN PUT IT BACK WITH DIELECTRIC SPARK PLUG BOOT GREASE $1.00 IN AUTO ZONE . RUNS LIKE NEW GOING ON 5 MONTHS . _

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Thanks I will try it.

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good luck , or else its a coil or spark plug going bad