Why does air conditioner compressor cut in and out on 1998 Mercury Grand Marquis

the low pressure measures 150 when compressor runs for about 10 seconds pressure drops to 125, is there a high pressure switch on the high pressure side?

Asked by for the 1998 Mercury Grand Marquis
low pressure should be around 30 haigh pressure should be around 150 you have poss severla issues seek a diag and est
That's what I was thinking. thanks