1985 1.9 liter

After changing the coolant, I started the engine to get it circulating.  I
turned off the engine for a minute, then tried to start it again.  The
engine turned over but no start.

I checked all the usual suspects, including 2, 3, and 4 spark plug.  I
finally found a split in the intake boot and ordered one, even though I
doubted it was the problem.  With the air flow meter and air filter box out
of the way, I decided to check the #1 spark plug.  As soon as I touched Jay
Brown's remote starter switch, the engine started on three cylinders.

The air filter is clean, so it must be the AFM.  Is there anything I can do
to try to get this one working or is it time to buy a rebuilt AFM?