I just picked up an old 93 s-10 blazer, and in order to start or to turn off, while in park, I have to push the shifter up in order to move the key either way.

Anyone know what this could be or if theres a way to fix this so it will start normally?

Shift linkage is either worn or out of adjustment. Could be in the column or at the transmission.

Is there a quick fix or any easy way to take care of it, or is it a fairly large & expensive problem?

Also, is this something that will continue to worsen and could cause major issues down the road, or it'll be fine if I can live with holding up the shifter?

Thanks.

Depends on what the problem is, that will determine if it will get worse or cause other issues. Nose around a little, you'll find something, then post back what you find.

My 93 S10 Blazer does that also. It is not a problem, just extremely annoying. There is a cable or spring that holds the shifter on the column and one day I heard it snap. Thus having more play in the shifter. Since my steering wheel cover is solid along the shaft, it seems much more of a problem to try and open it up and fix it. It will be fine like it is indefinitely, unless something else breaks or wears.