High idle

So I recently bought a 92 gs and it had a bad valve and I rebuilt the head. Replaced all vaccum lines, fuel filter, plugs, wires and all the small things that go along with a rebuild. So when I started the car it would idle very low so I raised the idle and it ran fine but then later that day the cel light came on and it jumped from 800 to 2000. So I shut it off and went to check the light and nothing so I turned it on and it was fine then it came back on and again same thing. So I scanned the light while car was on I and it came back with code 5 and replaced map but same thing etheir way. Any help will help cars on my last nerve.

Someone help plz will to try anything

its possible that you have a leak somewhere. also when you replaced head did you change intake manifold gasket as well as put a new throttle body gasket on. these gaskets should never be reused. also try swapping out the map sensor with another one any honda one will work that is firewall mounted 88-00

its says your by lansing im located right in bing. lmk how you make out but email me bc im not on here much. zas5987@aol.com