I have been having an intermittent RPM droppage at red lights that I've been trying to diagnose. This started after I dropped in a crate rebuilt motor last August. Didn't have the problem with the old motor.
At first I thought I was losing fuel pressure so I dropped a Walbro fuel pump in but that didn't solve the issue.
I pulled the stock Motorcraft ignition coil the other day and put a high performance Accel in. I saw a nice boost in power but the car did have one RPM drop episode after putting it in.
Today I pulled the cap, rotor and wires. I had stock motorcraft cap and rotor and MSD 8.8 mm wire set. I had put new Motorcraft platinum plugs in when the motor was dropped in.
I put in stock Motorcraft cap and rotor and Ford racing 9 mm wire set.
This is what the cap and rotor looked like when I pulled them. I didn't change them last August when the motor was swapped but I cleaned them with sandpaper and re used them. This is what they look like after 6 or 7 months. Not a daily driver so its not been run everyday.
What caused this kind of crustation in the cap and breakdown of the rotor and is the cause or the symptom?
For the record, after changing the cap, rotor and wires I drove the car a mile to bring to operating temp and ran code scan. Ran all 11's. No codes at all.