A DTC 16 indicates no low resolution pulses from the opti. In your case it's intermittent, that code will disable the injectors and spark, but will not light the SES light.
You can reset all DTC's in Datamaster and see if it returns. If you aren't experiencing any problems, the code shouldn't return. If it does, you will need to diagnose the opti and wiring.
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1995 Firehawk #528 resto-mod underway
Planned 383 rebuild: 195cc competition LT4 AFR heads, custom cam grind (still debating specs), 6" or 5.85" rods, forged internals
Upgraded T56: Viper mainshaft and 2nd gear, steel 3/4 shift fork, Billet keys 1-4, bronze shifter cup, internals Cryo'd and REM'd