CEL out, cannot pull OBD1 codes. How to fix?

[fixkick]

I have stock tires and no aftermarket lift or anything on it. The speedometer is only like 1mph off (if the State Police's speed sign is correct haha). It has P205/75R/15 97S tires on the front and on the back. I was going to replace it with all of those if I can find them.. (if not then is putting 215/70R/15 close enough like I saw someone else say?)

Furthermore when looking up spec on this I actually saw that is called for the 205/75/15 on the front but then 195/75/15 on the back. Mine's the part time 4x4 so the rear does the pushing. (I understand what the letters numbers mean: Passenger vehicle, 1st # being width in mm, 2nd # % of width the sidewall is high, Radial, then rim size and the number 97 after is the rating for it--- but was always under the impression that if you did have different sized tires on the back, then larger? or am I mistaken? i definitely though it odd to see a slightly narrower, shorter tire on the back.) tires are different too USA from say EU but are are matched ! no 4wd bucking allowed, and equal braking and steering at any speed, is a goal. (ABS is even more strict)

I do need a Service Manual and I'm going to spend my day off today pouring thru your site, thank you for the shortcuts! Cat is not visibly damaged or rusted. When I get the hoses, I am also going to get a small piece of tubing so I can listen like you have described! I followed every single bit of both of these replies and I'm re-reading it after I read the relevant manual for each part that you have made- to make sure that I'm not missing anything.

thank you so much for the advice and the tips/tricks and the time you've spent replying! I'm nowhere near a trained ear or tech but still with the info I gave you, via the net, you were able to cast a wide net and give me ALL of the information that I need to get me going down the right path or at least keep me busy for a little while replacing things that are definitely bad while diagnosing other things that may be.

I can literally feel myself becoming smarter every time I talk to you because I find myself looking at the inside of the car differently (I'm identifying things that I didn't know before like MAP vacuum hose, hose leading into throttle body for example is GRITTY to the touch and absolutely has to have some small cracking in there somewhere even though I didn't see it) Point is? Im replacing some hoses FOR SURE.

I also don't want to say too many more symptoms that I'm experiencing (I got most of them but the problems kind of evolve. If I notice it one day it will still run but the problem will just slowly get worse of course until I fix it. This car WANTS to run!! I swear it does because it gives me subtle, then not-so-subtle warning BEFORE something goes bad AND i'd even swear that this car is giving me the time to get the money together it seems!) But the point is that until I replace the list of things that I know need replacing already then I may continue to say something like "i smell exhaust when I let off of the throttle" and then later on realize I should have said "exhaust is generous to call it. it smells more like a mixture of raw fuel, exhaust, and slightly light burning plastic when I let off of the throttle". and once I have those other things fixed then we will know what it is not at least for now..
If you had a 4 or 5 gas exhaust analyser right no the AFR would be (hot 180f) engine , pegged, 10:1, or worse not 14.7:1 spec.
if you smell rich it is.  for sure. cat or no cat.

from what you've told me, and it's not this simple I am sure as there are multiple things that need replacing that could be causing just part of the total "not running right" (expertly worded lol) condition... but it sounds like:

1) I definitely have a bad o2 sensor.
2) I definitely have fuel pressure issues (low) likely caused by a clogged filter, but it could also be a failing pump. I lose RPM's going uphill so I get into the throttle more which I feel like may be sending raw fuel out of the exhaust when I, then, let off of the throttle going back down hill? Is it possible that the way I am having to drive to compensate for the clogged fuel filter may be causing that fuel-rich exhaust smell?
if misfiring up hill that is bad spark or way to rich fueling, (spark gap is 0.028 never 0.045" as it is OOBE (out of the box expiernce)
if lean , up hell the car will not misfire, (felt or heard) it will bog, like dragging a 10,000 lb weight up help,. (or called gross lack of power but is smooth no violent)

3) something likely downstream of the o2 on the exhaust may be bad (since there is already a new muffler) I'm thinking dead cat. I'm going to check it out for sure how you told me and if THAT is the problem then I will be fixing it first thing.
ONly a melted CAT will be a problem the this engine or ECU can tell the Cat is good or bad , as 1996+ can, no it  can not. you need no cat to run and get 80HP.


thank you for the advice on this as I literally got on here this morning to tell you that I suspect you're right bout the CAT and it's clogged/melted or at least failing OR that something else wrong is causing exhaust-smell symptoms. (if the cat is not melted inside and clogged) the ENGINE ECU is running rich, if too rich the engine misfires, (spark foul out rich)


I'll get on the filter and o2 sensor first as well as the hoses and I'll check the catalytic converter/downstream exhaust PLUS check capacitors on the ECU for damage. Again, thank you so much especially for the trick on unplugging O2 sensor for now to fix the condition, or erm well to fool the ECU by changing the 0v condition. i definitely understood that! my dad, luckily, taught me to think outside of the box so I am pick up on little hacks/tricks and understand the system as a whole, at least)

the cat melt test is easy for sure with $20 vacuum gauge. 7ways there are, #2 is the vacuum test , the most cheap way.

The vacuum on any car with melted cat (4cyc, Non V engine) the engine will not start or will have horrid power. (like 1 cylinder engine)
The first thing we see is vacuum test, fails HARD as a rock, vacuum is low and is actually inverted, backwards,  clear as day if it runs at all.
As you can see the tests are based on what tools you  have,  even  old fuel pump pressure gauge for CARB cars, works for O2 Backpressure over 2psi is bad cat.

Josh

P.S. I found a 2dr 8v parts car 5sp (unsure of 4x4 or 4x2), someone warped the head on it but it has a new timing belt and new tires (plus the full sized spare that I need) $400 for the whole thing. I was just about to get a new set of tires anyways ;-) So luckily I am in a position where I will have access to the "hard to find spare parts" you have listed unless of course they're out on both vehicles lol. Neither is rusted badly but.. you know, hedging my investment with a parts car haha :-) (nothing is better, ever than a parts car !)

if I didn't have access to your site.. I would not be able to do this. Thank you again SO MUCH. YOU ARE WELCOME !
You help regular people like me. I'm a home health nurse actually: help keep people home and out of those horrible nursing homes. I don't do it for the cash, that's for sure, so you help me a lot by being able to work on my vehicle. Before this I had only ever worked on the 3800 series GM engines. These pre-96 kicks are much so much more simple and the parts so much more cheap- but you are the missing part. so thank you for what you do for us all!

Your are so welcome, Josh and glad to help.

yes, the front and rear axles must be the  same ratio and if not same,  in 4wd the car will buck like mad  in real 4wd
and be a big danger to all and the same is true using tires that
are not the same circumference. (in 4wd) (2wd no problems)  "real 4wd means the front locking hubs are engaged and actually work (rare this old)"
see chart 2, here, link below:

https://fixkick.com/part-time-test.html

great the   mile marker test works agains ODOM, (or GPS)  very cool you did that , thanks.

fuel pressure on 8v is 100% altitude only device, and called FPR, fuel pressure reg.
key on and running pressure is are same 34-41 PSI (seen at the filter 6mm bango port this is input to fuel filter and if clogged filter pressure  goes to 60psi and less to the TBI. (where you check pressure matters, and is not easy ,not doing it at the banjo test port)
the car has no under hood test ports, at all. like 16v has.(if added to rail port, not seen  on any 8v)

at sea level here is my 8v.
the PSI does not change with throttle angle. like 16valves does.  mine was 38PSI. not going up hills huge.




Great a parts car !,  no better thing exists for sure suzuki;'s  next unborn child prices...  TB goes for $1200 and so does a mAF sensor on 16v.
hints.
on all g16's make sure the front 17mm crank/cog pulley is at 94ft/lbs (CW tight) never let it get loose. or  wrecks the crank, (TSB covers that)

---

RICH running gas sucking pig causes; (hope I get them all for you)!! WHY IS BELOW:
below:
The way this ECU works is that it loves to blow up CAP.'s.  rule#1 it not already RECAPPED, those caps love to fail,  and if black skinned tagged, as Rubicon, sure.
leak, crack,blow up, or go drive.  we put in JAPAN made CAPS rated at 105C and they work fantastic.
seen here:  https://fixkick.com/ECU/cap-source1.html

 
First is a bad Thermostat, if  not 180f hot or more the engine will never run right with any bad thermostat and they have life span 7 years(says STANT™
Then sensors,
The ECU like this has only few sensors that make spark work and fueling correct.
Rule2: is the ECU has no AI, it has no real savvy smarts at all and can only see dead sensors, now weak.
if the ECT sensor does not read 300ohms on 180f hot engine, but say reads 1000  it will run rich fuel, (or thermostat is bad and water is at 140f ops)
The next sensor is MAP if the hose leaks air the the MAP sees low vacuum and the map reads low and fuel goes rich. (the ECU just thinks your driving fast are are not doing that say you are parked in driveway)
O2 sensor , bad. (they are designed on purpose to fail safe, safe means 0vdc, failed. this prevents lean running engine and say not burning up valves but more important is not going lean and filling the world (hood) full of NOX gasses, nasty,  rich is way less nasty than NOX , NOX is acid rain and burned lungs.
next is IAT this is a super fine trim on the fueling, mostly a never fail sensor  like MAP, and runs cool so lasts unlike ECT (this old)
The next is CMP, cam sensor in the distributor if dead there will be no spark again.
If CMP goes dead the ECU sets a DTC (41/42 or both) code and cuts all fuel, so there will be no fire cause by NO SPARK.
and last and super common cause of rich.
LIMPHOME. (or  worse BACKUP)   we always look for DTC errors first due to bad limphome effects and for sure RICH running.

The ECU , if the CEL glows running, 99% that is limphome and runs super rich,  horrid rich can be. sinks of unburnd fuel. running and with dead cat, black cloud effect at end of tail pipe.
The Backup mode, makes the CEL lamp go dead, 100% of the time key on or running, this is a hidden 2nd ECU inside that is super super rich and bad.
This ECU is OBD1, and all codes are strictly  only SUzUki and is not a standard, like OBD2 is.(P0xxx) codes.
The 1996+ car would set DTC for super rich and tell you fuel trim is DEAD and MORE. not your car, this year.


The ECU checks its self as it boots if the main ECU brain is dead it then goes to BACKUP mode.  (rare but something to know once the CEL bulb works again.
top causes of dead CEL are, bad lamp, some bad guy removed it to hid DTC errors (super common), or is in backup mode.

RICH, (more facts...) trying to post them all for you.
fuel pressure  at 60PSI all the time (bad FPR) yah it will run rich as a piggy mine ran at 38 full time.
leaking TBI injector, (not you, you proved it is ok)  you are good here.
your fuel pressure is 40 and is perfect.  
as you can  see some kicks have 41 PSI FPR on a good new car, so if the O2 goes dead. it can go a lot richer,  (see how?)

is your car with 02 , 3 wire? sensor.  the BOSCH # for this car, is 15701-3 (3=3wire my code not bosch) the Bosch universal is 15726-3 (best price is this)!!!
O2 is complex buy, Fed/CALif and TBI or MPI versions (MPI=MFI) see here. you want only TBI !
You need, G16kC (the "C" ,means canvas top 2 door. TBI. (tricky no?) KV = van = 4door, no buy MPI. (4 injector engines)
The stores think both G16 engines are the same they are NOT. ( I also show all sensor colors used by all brands so one can make substitutions &easy save cash)

is your hood sticker with California words in the text there if not the car is fed and the nag switch is there, and if there as all are fed, the last owners drove car with CEL glowing for years not know what it is and burned the lamp out. best Idea is remove the nag switch first thing you do when found.

this thing (FED ONLY) plugs in to rear side of he cluster,  and just unplugs.  best is remove it, there is no need for it or any side effects at all.
https://fixkick.com/CEL/NAG-Lamp.html


DAY 2 I remove this, I do no like things to impede on the road failure diagnose, in the dark and driving on ice, 100miles from home, if you get my drift.

if this switch is active it blocks flash codes and is why I do not like it or crawling under the dash every 50,000 mile to reset this "legacy Joker" Leaded fuel JOKER.






see words SZ that is the nag jack.  may be tab locked,so pinch it pull it. out. (locations vary for switch and back of speedo) but all plugs same,



not seen on any California car ever. the NAG is FED only joker.

that is my rich running engine thesis, to you.  hope it saves you lots of cash and trouble and labor.

Cheers to you  !


PS the 8v is more simple and more easy to fix and diagnose. (most parts are cheaper, for sure than new cars but my key parts are not sold now for it )
2 hard parts to buy are Throttle  body, and new front wheel bearing hubs. (and some engine parts hard too.(inside)

 
it has no 3 extra injectors to clog or leak.
It has no $1000 MAF sensors, and endless bad clones sold for it.
It always makes  more power with vacuum leaks unlike ,16v goes lean and goes weak power.
This engine and ECU just wants to run no matter what.
the 8v  exhaust manifold does not crack as the 16v all do.
keep the 17mm bolt tight,
and run mag HV spark wire for hotter spark. (avoid carbon or silicon junk wires)


(1 view)"susuki fail safe"
LIMPHOME mode, runs no spark advance or nill,  and wastes tons of fuel.  this one line tells you, fix the Dead LAMP CEL.
avoid the LIMP, for sure, no matter what fix this first.
if the car drives mostly ok and stops ok (not skid or pulling) and does not leak fuel or brakefluid ,fix the DEAD CEL.

all the best to you and others !