The code doesn't come back right away when I clear it, but sure enough within a few days it is back at code 5. On one occasion, it threw codes 10 and 26 a few days after I cleared 5. When I cleared those, code 5 came back.

I will definitely have to look into a compression check. This car has been idling rough for a very very long time (it was a family car that just became mine) and I have managed to smoothen it out by putting in a new voltage regulator, new gaskets on the air intake, and a new air filter. Currently I feel the car revving up and down between 600-700 rpm when warm, and then it dips down and idles real rough. It only occurs in drive and I haven't had the chance to look under the hood while its in gear, so I don't know about how much the engine shakes. I plan on replacing the mounts after I get the codes taken care of. We will see how it goes