1989 Chevy Blazer, just had complete service performed 2 weeks ago. For the first time, my "check gages" light came on. I noticed the oil pressure was zero. Never saw this before. I check the oil (and while it said to add oil (weird since I just had the service), it still had oil on the dip stick. Is driving dangerous? Will my motor burn up? What shall I do?

Just check your oil every other day or everyday make sure that its up to specs bring it back in and tell them what the problem is clearly you just paid a lot of money and they fuck your shit so tell them about it your cars going to run fine it's probably just a sensor oil pressure sensor switch

First when you check your oil level, is the vehicle siting level? Make sure the vehicle has sat after turning it off for a few minutes to allow oil in the top of the engine to drain back into the oil pan. If you still do this, they just may have put the correct amount of oi8l in bout forgot to compensate for the oil the filter take, usually a quart. Fill it to the full mark only. There is a small wire that attaches to the oil sensor that travels to your instrument cluster. Make sure there are no dangling lose wires visible. The sensor wire just may be off or burned or broken. Take it back to the shop you had them perform the work, IF YOU TRUST THEM, and have them check everything out.

To be sure, I would insure that the oil is actually pumping. If oil isnt circulating, you are headed for big problems.

Go back to guys who screwed you over and demand justice or keep oil in it.

Sounds like you took it up the wazoo on the “full service” Go tell them dudes wats up.