If code #20 will not clear, and/or keeps recurring immediately, the FSM says to replace the EZL - see below.
Click here for the full PDF that screenshot was taken from.
Seems like code #20indicates the EZL will no longer properly store/display fault codes, although it may still function correctly. If you are interested in buying a known-good/tested replacement EZL, drop me a line (click "start conversation").
In the meantime, replace BOTH coils with new Bosch, and closely inspect the rest of the secondary ignition system as doolar mentioned above. In particular check for oil leaking from the cam solenoids and running along the bottom edge of the distributor cap, along with checking for liquid on the back of the insulators. Either of these problems can cause intermittent ignition issues. Adding vent slots to the caps is generally recommended (
click here for details) but if there's an oil leak, that has to be remedied as well.
BTW, welcome to the forum!
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