Which fuel do you use more?
Is it a knock, or more of a rattle. If a rattle, it's probably detonation - back the timing off a little. Will lose performance on gas.
If a knock, probably not timing
check things like vacuum supply to regulator and MAP. TPS voltage, etc.
Proud TQE Operator and President of SEFAG - the Society for the Elimination of Ford Automatic Gearboxes
Pacemaker headers + 2.5" exhaust
EF Fairmont interior
Lowered King springs
5 speed manual
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