I recently replaced the spark plugs in my Frazer with another set of Motorcraft A7C plugs. The previous set had been in for a few years and the reason I replaced was due to cosmetic issues (rusty). I cannot find a definitive listing of applicable spark plugs and have relied on my Motors Book or shop manual. When I first got involved with KF products, I remember AL7C was the norm(?). Is the A7C ok to use or should I be using another plug?
For some reason now, just because I replaced the plugs some driveability issues have surfaced. I found some green corrosion on the distributor cap end of the wires so I replaced with a set of repro wires purchased from Carl Herring. I also replaced the cap due to some light corrosion issues. The car had been running ok until I changed the plugs so I am confused over why it now feels like its running on 5 cylinders under load and the exhaust seems to 'blat'. With the help of a knowledgeable friend we rechecked the firing order, replaced a leaking plug wire and rechecked the carb adjustments. The only other link I can think of is the coil which I have no idea how long it has been on the car. Do they tend to break down with age and engine rpm? If that is the case, I do not find a separate listing for the coil in an autolight ignition system.
Any help or suggestions would be greatly appreciated. Again the car seemed to be running ok until I replaced the plugs recently and am thoroughly confused over this.
