Black Soot on Spark Plugs

[ezgotxtman]

My 2005 EZGO TXT didn't have any black soot on the S. Plugs until the EZGO factory team did the recall program.

My 295cc 4 cycle was running fine with the BPR4ES plugs, gaped at .028-.030. They looked fine with some (slight) black soot on them, but that seem to be normal for the past two years.

Last week the EZGO team made the air box recall that should have been done last year (just now getting to it after many a phone call) on their recall program on this model year.
They removed the factory (flat) air box and filter, installed a baffle plate and .etc, plus a new (different filter system), and new FR2A-D spark plugs.

Now the new FR2A-D spark plugs are coated (thick, not oily) black soot. So bad that they are hard to remove from the cylinder head.
They did not install a new carburetor, just replaced the original one, and did no changes to the carburetor adjustments. I was told they would install a new carburetor with this new recall program.

So, any guess what can be done to eliminate this soot on the spark plugs?