I have an older house with some outlet plugs that don't have the ground third prong. Some have the older 2-prongs. I'm in the process of changing all plugs and switches to the decor style. I want to replace this 2-prong outlet with a 3-prong outlet but when I test it its an open ground. Without having to run a ground wire to this plug, is there any other way to properly ground this outlet? Any ideas?
No the receptacle (plug; outlet) cannot be grounded without running a ground wire.
But there are other things you can do to make it safer, for example put a ground fault circuit interrupter on that circuit.
Older conduit and BX cable installations that may have had the metal sheathing forming a ground path may or may not still have a reliable ground path due to oxidation, loosening of screws and clamps, etc.
If you want to put a three prong receptacle there and not string a ground wire then you must put in GFCI protection and also label each affected receptacle with "No equipment ground, GFCI protected." One GFCI unit whether in a receptacle unit or in a breaker unit can protect several receptacles downstream or even the entire branch circuit.
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.