Need some help

[fixkick]

correct 8valve TBI FED car it is, one injector
no need at all for CALIF thermo-probe EGR but does work if installed, sensor there doing zero, both EGR valve work on the FED car, for sure, (do not unscrew the thermo probe from valve.)_
this car is OBD1 not 2,
so you can not use OBD2 anything here, just the flash codes at the DLC jumper
1996 is first care with OBD2. for sure
cat must  be installed, and Calif will see its gone at visual inspection. and code 51 tripped.
the dash gauge has not temp marks at all it is just  to show gross overheating, and such.

DOES CEL glow key on, and not started, this is step 1 on all these cars this old,  ?

lots of reasons to be rich,
thermostat is one,  not 190f  a  7year  life scan part it is.  Design life (wax pellet based)
fuel pressure too high
leaking injector. there is only one here
ECT sensor not showing 300 ohms hot with working themostate, higher ohms is cold engine.
spark timing wrong,
bad spark plugs  or its wire set .bad (carbon wire suck for life spans, mag core is best)
compression way way too low or timing belt on cam slipped, and compression is horribly sow not 160 PSI but is 100 or less.
that is about it, air cleaner packed in mice nests.
good luck

The CEL only glows when keys are in, engine off. When engine on, the CEL is off. I will check the thermostat and ECT sensor


ALSO - I will be ordering a california compliant CAT from rock auto. is there a downststream O2 sensor that I also need to order? I see an 02 sensor on the exhaust manifold right now, is there another one that goes further downstream by the CAT?

note at ROCK and others they never asked you what engine is there!, at all ,so they list wrong parts endlessly, (be sure to shop  carefully)
only 92-95 8v parts matter here.  not 16v and for sure not 1996 up. ever.  
in 1996 the 8v was banned by our EPA. and OBD2 born same day.

all cars USA first down-stream O2 is 1996 , by USA law EPA.
and not before, (some rare fords 1995 sure but we are suzuki  onlY)

only 1 O2, on the top of the exhaust manifold 8v. just one. (learn to buy the correct O2 , 3 wire or 4, not he same and matters)
all fuse injection is controlled by this one sensors. hot. engine.
the engine needs to be hot first,  180f, this is EFI rule #1,  all ease is secondary to that.

i use an IR gun to do that, and for sure hot ECT sensors 300 ohms seen here, in my chart my secret voltage checks
see 300 here, see volts 0.65vdc?  (ohms only pulled hot but volts works full time connected, hot. the volts tells you temperatures if ect not bad sure.
https://fixkick.com/ECU/temp-sensors.html

now the IR GUN

top tank , best done after 10 mine run to get full temps correct.  idling takes forever, to attain this test.


https://fixkick.com/Cooling-engine/rad-top.jpg


IRgun page
https://fixkick.com/overheating.html#IRgun


code 12 is no bad sensors,  this is  good start.
no vacuum leaks to the MAP or clogs  allowed.

fuel pressure at speck, idle is 34 to 41 psi
fsm spec here.

https://fixkick.com/INJECTORS/PUMP/8v-fuel-press95w.jpg

keyon  idle or wot all the same,  this is controlled by altitude only this range

qod:
the car is fed. why calif, cat,
the cat will not fit I bet,

the cat needs only be Three way cat TWC.  
Calif versions use different mounts and headers on some.
buy only cats for  your 8v, and FED , it is TWC too,

nobody is required to convert any fed car to calif. never have I heard that nor expect it.

now see my complex 02 chart, super tricky but sure 3wire it is

https://fixkick.com/sensors/OxyGen_senso...#oxy-parts
-56B00 (suzuki)
15726-3 (bosch I added the 3) universal, with pig tails and splice box hack. (it works but take hand splicing and wires connected 1 by 1 correctly)
15701[i][b]-3 (bosch PnP with suzuki plug actual, nothing works better  or  more easy, just  plug it in)[/b][/i]

my page there shows all secret wire colors by suzuki and O2 makes.  link just above.



the sensors at rock auto most are wrong all with 4 pins are dead wrong and for 16vdc, for  10 years now wrong. (asked them many a time to do engine types, no fix yet)


what I do is pick a brand, NTK is good (PART OF NGK spark plugs etc) bosch is great but all versions of their sensor are not at ROCK.
there catalog shows 2 kinds 1992 , 8v and 16v, soft top , hard top (hard means 4 doors)

NTK 21541 8v soft top
NTK  24617 16v hard top

make sure the connector matches your cars harness plug, 91 below but looks same , the one and only O2, in the lens.
8v only and 3 wires and 3 pins and be sure plug matches exactly (some show 4 pins at plug but under closer view 1 of 4 is empty.