Car stalls at lights. Check engine light on. Running lean on Banks 1 & 2. MAF? on 1996 Ford Thunderbird

When car stalls, it starts up again no problem. I also notice volt gage drops during the rough idle before stalling. Told it could be a vacuum leak somewhere along the line. This problem does not happen but occasionally.

Asked by for the 1996 Ford Thunderbird
yes vac leaks will cause this and so will mass air flow. have a smoke test done b4 repl maf could also be fuel pressure,inj issues or plugged fuel filter
Thanks for the response! Btw, I had the intake manifold replaced since there was an issue with these.
if the intake is not sealed correctly it could be the prob also