ok I PUT NEW PLUGS AND WIRES ON MY CAR A MERCURY GRAND MARQUIS 1996 4.3 V 8 ...IT HAS A MISS NO. 5 CYC. IT RUNS PRETTY GOOD AT AN IDLE IS OK YOU CAN HEAR THE MISS ONCE IN WHILE WHEN ACCELERATING THE CAR POPS AND BACK FIRES THE CODE READER SAYS SOME THING ABOUT THE TRIGGERING SYSTEM ON THE COIL CAN ANY ONE TELL ME ANYTHING ABOUT MY PROBLEM PLEASE SOME ONE GIVE SOME KIND OF A RESPONSE EVEN IF IT IS I NEVER HERD OF THIS THANK YOU JOE
Hello - no, the coils cannot vary timing, they are responsive to whatever timing trigger is passed to them (crankshaft or camshaft position sensor, ignition control module, distributor, etc.). The coil which services Cyl 5 could be failing however - try swapping the 2 coil packs and see if the symptom moves to another cylinder - if so, you’ve found the problem (coil failure). Misfires are tough to trace and can vary as to their cause from junk in the spark plug well causing a short, to plugs, wires or coils, leaking or clogged fuel injectors, to blown head gasket leaking coolant into that cylinder. Popping and backfiring are usually indicators for an air leak (lean condition) in the air intake. I would recommend a misfiring inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
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