'89 Civic Si hatch - CEL code #5, dies after 20 seconds

[Psych Nah]

'89 Honda Civic Si hatch - 1.6L D16A6

Start it up, it boggs really bad sometimes cutting out all the way. If I give it some gas for a second it will run healthy for about 20 seconds, then slowly cutting out. Having some problems with fuel delivery? Would be my guess...

Anyway, the idle has been jumping around for the past couple weeks. Tried numerous things, still running like crap. I was getting CEL code #3, then #5...
#3 being "MAP sensor or circuit elecrtical fault"
#5 being "MAP sensor mechanical fault"
Not completely sure of the difference...

Hit the salvage yards, found a couple different MAP's. Tried them and now Im just getting CEL code #5. (Trying to avoid spending $230 on brand new MAP sensor alone) I just replaced the spark plugs with some basic single prong platinums...the ones that I pullled out were 4 prong. Definately not a good choice of plug for NA A6.

Fuel pump?
Bad gas?
Injectors?
TPS sensor?
Speed sensor?

Im lost, and almost fed up with messing with it. Help me out here.
Thank you in advance.

[festivagt]

Vaccum leak? Misadjusted valves? Bad wiring to the map sensor? Any of the wiring in the car ever get messed with? Check your engine grounds and make sure they are good and clean. A low vaccuum reading will trip those codes too. Rememeber a code SUGGESTS an error with said component or said system related to the component. Keep us posted.
HENRY

[Psych Nah]

Had a buddy from a shop run a diagnostic on it, ended up being the coolant temp sensor. Returned the idle air control valve, which put a buck seventy back in my pocket. Map sensor also had a vacuum line switched around. Had to be something so simple made things so complicated.