Could really use some help

[fixkick]

I remove all nag switches, to avoid the complex answers, and usage.(confusion, etc)
the nag switch is miles timer, and is 100% useless in 2016, it was for the long ago GONE, leaded fuel.
the NAG lamp comes on ,you go to suzuki and they check the cars CAT for Lead damage.
http://www.fixkick.com/CEL/NAG-Lamp.html
If you slide the switch and the CEL lamp comes on, that means it's in NAG mode (maybe) then slide so CEL lamp is off. means CEL is off.
Keep in mind key on, engine off the CEL glows this is called CEL lamp test mode.
the lamp is shared with the timer and the ECU CEL function. (a pain yes)
i unplug the 3wire 4 pin nag wires, on rear of Speedo and this pain ends. and now only CEL works forever.
but you can live with it, sure,
just insert the diagnostic jumper, and the CEL flashes, if not move the NAG switch to the other side and now the CEL must flash.
the jumper is here. most 8v cars have the 4 pin connector next to the battery.
http://www.fixkick.com/CEL/DLC/DiagJump.html
see this page, there is a 4 pin conn. and 6pin, you have one or the other for sure.
the stock car has a cover over it a rubber cap, for protecting its 4 or 6 pins
you then use paper clip, (shinny metal never plastic covered or colored) forming a metal jumper wire clip and short the 2 pins , as seen in the link above.
12 codes are good.
if not 12s, the ECU can be limphome mode, it must flash 12s ,12s are a GOAL.

most early 90s cars have have this DLC connector jumper. and flash codes, until USA laws, kicked in in 1996. (1998 in canada)
The ECU reports all sensors, that are dead. that is about all it can do. for diagnosis, but we look first. never ignore the CEL.
IT will also report a weak/dead EGR system.

ok 8v engine top , black steel , with 1 injector in the throttle body , that works totally different than the MPI engine,
so if you insert the diagnostic jumper in the DLC connnector next to the battery,does it flash 12's (means im kinda happy, the ECU)
it must flash 12s or something or the ecu is sick (bad caps disease)
Engine coolant get fully hot?
check fuel pressure>? at the test port on the banjo fitting of fuel filter, its fuel pressure test port, 60psi bad, 30 good. (ball park)
34-41psi, is spec.

The CEL light does come on with the key and go out when it is running. I know when I unplugged my IAT the CEL Light would come one. I have also jacked around with the NAG switch behind the speaker on driver side. when you slide it 1 way the CEL light is always on and the other direction CEL is off (until unplug IAT sensor). It may be in limphome mod but how do you know?

It is an 8V I believe. and i checked out the MAP sensor and the line to it seems good with no cracks and has good vac. I have not cleaned the nipple. what is the best procedure to do that?

Thanks for the help!!