my ltd crown victoria starts up but when revved it shut down what could that be
Restricted exhaust, low fuel pressure or flow, crank sensor misread, TPS intermittent open circuit, weak ECC relay, just to mention the most common. There were some of these models that had the nightmare MCU systems and not many shops would work on them so I hope yours is just the old Ford OBD 1.
Might be that the alternator just can't keep up with the faster spark at higher RPMs. Have the alternator tested.... Or maybe the battery is near dead and is stressing the alternator that's trying to run everything electrical and recharge the dying battery, as well. Have the battery tested too.