What's the worst that could happen if.....

[SuzukiGhostRider]

You pull a stupid and forget to disconnect the scanner prior to engine starting , because you were distracted. I was scanning codes last night. Turned the key off, got distracted talking to the woman, made a few adjustments under the hood and told her to turn the engine on. Was a few minutes before I realized the tester was still connected. I discovered a miss also, last night. Cylinder 3. Plug is carboned up and probably fouled. But I can't , for the life of me, remember if the miss was there before or after I started with the scanner plugged in.
Car is an '88 Beretta GT with a '90 3.1L.

[IsaacHayes]

That won't mess it up.

I start my car in scan and code read mode all the time. It still runs the engine just fine :P

[SuzukiGhostRider]

I was pretty sure. My paranoia dictated a 2nd opinion. Thx Issac.

[3100 MPFI]

Done it many times in both the gold car when the 3100 was running as an MPFI, and I have even done it a couple of times to my 1990 Grand Prix STE. Does not hurt anything, but I know that if you do that in a Cutlass Supreme that has the DIGITAL GAUGES CLUSTER, then the tach does not work until after you unplug it, and also, the DIC will display DIAGNOSTIC MODE.

[01GPGT]

my 85 monte was such a pos i left the paper clip in there 24/7 so i could see if a new code popped up