I am still trying to get the engine to run smooth.  It has been surging on me.  With fuel pressure steady, the mixture and the RPM jump around a lot (I haven’t started taking exact readings yet, still trying to reduce/eliminate surging). 

 

Today I tried swapping around the vacuum lines, and as an afterthought, I selected the B controller, and the engine smoother out, and RPM jumped up considerably.

 

So I am wondering what the difference is between the two.  What are the extra things that A looks at that B doesn’t?  This will help me figure out a troubleshooting procedure.  Maybe I can isolate the faulty component.

 

I looked through the EC-2 manual and couldn’t find anything listed.  Maybe I missed it.

 

Chris