Misfire, but no DTC's?

[Fabricator]

so you CEL lamp never glows running?
keyon glows, start engine, CEL goes out and stays out. (but in canada the CEL/,MIL lamp lies to you, just the lamp not the scans) ok?

Yes - CEL on w/ key on, goes out when started and stays out

see this. here is my 96, this and the vin tells me what that X90 had day 1, new, and for sure what transmission.
http://www.fixkick.com/specs/Body-TAGS/h...age_9.html

see the word EPA there, this tells me lots too.

the 4speed automatic (DO you have that?) 5-speed manual trans - sorry for not mentioning earlier
The OD lamp in 4speed car flashes if the TRANNY is sick. but will not cause the ECU go nuts , in 1996, only on 1997 up.
uses this DLC for just it ( there are 3 DLC on this car) OBD2 DLC#1 , 4speed (if fitted)#2, and under hood DLC#3 for spark and idle controls.(at right Front headlamp rear, 6 pin DLC)
this front DLC3 at RF headlamp make very sure no jumpers are inserted in this jack, (see plug there with rubber cap that is DLC)
92-96 only and only 4speed box.
http://www.fixkick.com/tranny/slush/slid...conn1w.jpg

in 1997 they deleted this jack #2 and moved TCM brain into ECU brain and called it a PCM. and now fails for smog USA if this TCM shows errors.
in1997 , tranny errors show up only in OBD2 scan tool port. and can do limphome mode just for the tranny.

[Fabricator]

driving cycles are not simple, like keyon , key off, key on, be nice if they had DLC jumper to do that, called, (driving cycle disabled)
but due to that , DLC are a pain in the bottom gasket.
btw, i will study your xls more completely later today.. before 6pm.

http://ge.tt/6gvplbp2

see chapter 3 part3) (down load , the view online fails for too big ) P0300 misfire, 300 means all 4 fail and all 4 random failing. (so is most time AFR RELATED) BUT THERE ARE LEAN AND RICH CODES
page 11 +
300 MEANS weak piston;rod/crank accelerations, means combustion was weak ,or spark failed, or injector failed. (in this case all 4 are weak)
seem the frame 15 engine goes lean, to me, best I can tell in, openloop.
ON THE DATA FRAME 15 , AT WOT THE O2 GOES LEAN AND THE MAF IS WEaK, CLEAN IT TEST THE MAF MORE CAREFULLY.

why is MAF weak this is the focus point. Will clean and test MAF
the injectors could all 4 be clogged (1/2 way) PO installed new injectors, but do not know where he got them from - will ask
from bad fuel parked over a year. About 1/4 tank left, car was parked for a few weeks before I got it
the injector balance test may fail. Will consult FSM for injector balance test

DTCs go offline, if fuel level is below 15% (Page 11) 11 to 14 (are p0300)
P0300 needs steady (steady TPS) to run the monitor, idle or steady cruise. the CEL then blinks on USA car, telling driver, your cat will soon burn up.even melt. Looks like I need to add some gas and drive this thing...
below 4000 RPM rule (300's)
causes
Huge vacuum leak or weak maf or only dirty maf.
I'd say engine is going lean. (02 off line , I cant see it go lean thanks to tools OBD2,silliness here) My scan tool fancy I can force or even loop on 02 readings live. and 2d scope view them)
the injectors weak? theory,/? one can add propane gas to IAT port. to see of bog or misfire ends. Want to try this
P300 per page 11,. has 2 times rule in this DTC,
even bad fuel can do this. super easy,
page 11 list them all.
bad fuel
weak maf
vacuum leaks.
injectors 1 ,2,3,4 all weak, (partically clogged, due to bad fuel)
lean or too rich misfire.
and spark must be good, (got new plugs? set to 0.028 inches, J plugs only no surface fire plugs allowed on this weak spark system) Plugs relatively new, and are J style plugs
fuel filter 22 years old, and 90% packed up? if fuel pressure drops at frame 15, BINGO, Fuel pressure goes to 43# when misfire is induced

DTC's set for 2 ignition cylces (so 1 run will no set many DTCs) in general, one has to read all 4 parts, (PDF) to see all rules, I just OCR mine to find "cycle"
they clear with 2 to 40 driving cycles.
its not low fuel pressure. (so we skip this and is super common)


no P0171 or 172 trim errors (part3, page6)
I dont see fuel trim landing on 43% or greater long-term fuel trim or over 20% short term.
does you scan tool have, O2 sensor graph viewer? (this loops the scans on B1S1. bank 1, sensor 1 front, and see if the sensors goes to 0v,? lean? stuck lean. Scanner does have a graph view - check of 02B1S1 shows cycling rich to lean - no flat lines, and appears to operating normally? - I have a video showing this, but might be too big to post here...
if yes, MAF is week or injectors clogged

[Fabricator]

the tricky part here is car is not on the road, only load testing works, fully loaded car or up hill flogged (but fails parked, so that too is ok.)
so test the car parked, and gun engine hit, and for 3 key on cycles, hot. repeat 2 or 3 times see if DTC set !!! Will try this, but think driving would be better

to see if MAF works, but do clean it first.
if still fails after clean maf
test injectors, next. or pro clean them . like seen , reverse flowed, untrasonic cleaned.
https://www.witchhunter.com/


i just added this, and applies to P0300, 301 upto P0304 ( 1,2,3,4 code means only this cylinder fails.
so put more gas in take, over 15%
and run the test 2 times, hot engine gun throttle hard, parked, and see if P03xx codes POP, or P0171 or PO172 (rich lean pop)
even flog the throttle from 2000 to 4000 RPM (or if bogs still try)
or try to hold throttle steady at 3000 RPM or 4000 for say 10 seconds, see of DTC's POP, the 300s series only POP for steady cruise,



bad fuel
bad maf (dirty
vacuum leaks huge. (super huge, that is do not believe)
dirty injectors or filter.
I assume spark plugs new. at the tips white now or jet black carboned.?

even this cheap HARBOR FRIGHT(SIC) tool can loop scan the 02 front " Graph live data onscreen" feature set is very good to have. like this. (not sold there now, the have better ones , and brand changed) but is clear what is going on.
the tool is slow (or ECU is) and does not see all "crosscounts' but we know it does. on newer cars with CAN buss and faster ECu this plot becomes super perfect. 3 points on each swing is best.



great 02 demo here, even many cheap tools can do this even $50 (ask) ignore bank 2 comments and 2rear sensor but do listen to all S1 comments for sure
idle, cruise, gunned throttle and fuel cut modes(deceleration) lazy 02 or dead or stuck lean are all things to check and graphing 02 is the only way to do this.
https://www.youtube.com/watch?v=jRa752CeNvg

even my relic PALM can do O2 live, see? 1996 tool, I made with custom software, from friend.
http://www.fixkick.com/sensors/chev-live009.jpg

[fixkick]

The engine will not rev up fast. no power. lack of full power infact yours is pathetic, power.
what does it take with this car this engine.
engine must pump air compression ok CAT not melted,, and fuel pressure at spec and at spec, with engine bogging? , and MAF good. injectors not clogged, that is all it takes mostly.
The MAF is chicken and egg deal, it allows Acceleration to happen, for sure up a hill or>>> see next tests.

Your O2 does swing in CL but that only works at gentle RPM no load on engine, no TRANSMISSION STATED YET (the O2 is offline at WOT so we skip O2, )
the reason to look at 02 is all other modes of engine load, to see it works at idle and say throttle at 2000 RPM in neutral or driving say 45mph flat ground and see CL happen, ( bet this fails)
no driving allowed, as car is unsafe on the road, so ... we do it like this.
if this car is a AUTOMATIC we can use it for a DYNO, ever do that?
The built in VIRTUAL Quasi DYNO !
what does that mean well in the service manual is the 4speed stall test.
if you chock the wheels, and set hand brake, left foot on brake hard, right on throttle, and hot engine, in park ,car not pointed at Kids Day care center (sarc, pun)
shift now to DRIVE. (dyno mode, free) the only thing I like Automatics for is this.... fun test.
and the do the A/T TANNY offical stall tests, with scan tool logging data, for sure clean MAF.
We can plot maf/TPS reading, maf over throttle angle.
to see if the MAF shows more than 20 that you got before, the test 5 seconds max, reset for 1min repeat or you overheat the TC. (and ATF fluid)
http://www.fixkick.com/videos/FLV-all/showtime.html#MAF (seen here under maf/stall tests) grams/second,)
the TC limits RPM at 2000 (dyno load) and 21grams/second MAF readings, if maf is weak it ill not hit 20 nor 2000
when do this on tall hill , demanding 95HP from the engine 100% load grams/second on mine was 55 (96, G16b 16v)fully tuned up car, and perfect compression
at sealevel above sea level is less. 3% less per 1000ft. per pilots book. 55 is max, at sealevel.
the maf is a key sensor on this car,unplug it see if power returns, (but will that is limphome mode and spark advance is was as will be power)

my list from post 1.

why not do signature here,
like this," Suzuki X90, 1996, what transmission?, what drive line? 4wd or 2wd?"

and my red list?
NO TRANSMISSION STATED?
NO SPARK PLUGS STATED (J PLUGS AND gap SETTING at 0.028" not NGK machine set at 0.045" as all are.!)?
NO country stated, USA or Canada, the ECU is not the same in both countries, so I must ask country,sorry.
No new FUEL filter?
IS TANK FUEL BAD, IS IT OVER 15% FULL, IF NOT DTC do not set for P0300. (ok we know its not below 15% now)
NO outdoor temperature stated. please tell me that.

knowing this we can ignore vast numbers of tests. all wasted.

what is known.
engine is ok, it is not a bad engine,
my guess is injectors will pass the balance test and are not clogged but only based on 'new injectors put in"
the fuel pressure I guess is ok in frame 15, as it MUST BE.
the next is maf , clean it, really this is a 50k mile service point.
if car is driving on a highway fast or on 8 lane freeway,the air that lands on the car is nasty full of oil and crap, and the MAF eats that crap and cokes up.
in town car only not likely.

the maf needs to be cleaned using the can and straw with 8 " inches gap from end of stray to MAF . keep your distance,
and hit it 3 times, 1minute soaks each, time, or more, 5 even if filthy max.
what happens with a dirty MAF
it Under reports air.
and the ECU can not inject fuel correctly with any weak maf, and will bog'
one test it unplug the maf , go to limphome does power wake up, yes, MAF is bad. or just dirty, its just tuneup step on all cars with maf.
some cars have a MAF that self cleans, at key on, I do not think this maf does that. so is a SERVICE POINT or as old guys say TUNE UP step.
in short , weak maf or injectors clogged or low fuel pressure , at frame 15

[fixkick]

more maf bad news. ( all this is like first thing i do on any not new car, bogus parts checks, hacking signs, and parts missing)
this car is old, and was in the hands of others
and if you the old owner bought and put in a C4 CHina cloned MAF< well those are most times, junk >>> example:1 http://fixkick.com/sensors/china-maf/cloned-maf.html

the side of you maf has a label
58B00: (< usa maf , in Europe >57b, Air meters non hot wire)
this label; (not C4 brands) is marked with makers name, Misubishi, Hitachis or just suzuki, and this number marking,

today we have far better choices (unlike suzuki $1200 priced tag , ouch)

https://www.rockauto.com/en/catalog/suzu...ensor,5128


some cars are hacked, for sure maf end with cold air mod (malarkey to the max)
the maf is now not mounted at all, or still stock and bounces around like toy. killing the maf dead.
I cant see under your hood for all those things wrong, no can do.

[Fabricator]

The engine will not rev up fast. no power. lack of full power infact yours is pathetic, power.
what does it take with this car this engine.
engine must pump air compression ok CAT not melted,, and fuel pressure at spec and at spec, with engine bogging? , and MAF good. injectors not clogged, that is all it takes mostly.
The MAF is chicken and egg deal, it allows Acceleration to happen, for sure up a hill or>>> see next tests.

Your O2 does swing in CL but that only works at gentle RPM no load on engine, no TRANSMISSION STATED YET (the O2 is offline at WOT so we skip O2, )
the reason to look at 02 is all other modes of engine load, to see it works at idle and say throttle at 2000 RPM in neutral or driving say 45mph flat ground and see CL happen, ( bet this fails)
no driving allowed, as car is unsafe on the road, so ... we do it like this.
if this car is a AUTOMATIC we can use it for a DYNO, ever do that?
The built in VIRTUAL Quasi DYNO !
what does that mean well in the service manual is the 4speed stall test.
if you chock the wheels, and set hand brake, left foot on brake hard, right on throttle, and hot engine, in park ,car not pointed at Kids Day care center (sarc, pun)
shift now to DRIVE. (dyno mode, free) the only thing I like Automatics for is this.... fun test.
and the do the A/T TANNY offical stall tests, with scan tool logging data, for sure clean MAF.
We can plot maf/TPS reading, maf over throttle angle.
to see if the MAF shows more than 20 that you got before, the test 5 seconds max, reset for 1min repeat or you overheat the TC. (and ATF fluid)
http://www.fixkick.com/videos/FLV-all/showtime.html#MAF (seen here under maf/stall tests) grams/second,)
the TC limits RPM at 2000 (dyno load) and 21grams/second MAF readings, if maf is weak it ill not hit 20 nor 2000
when do this on tall hill , demanding 95HP from the engine 100% load grams/second on mine was 55 (96, G16b 16v)fully tuned up car, and perfect compression
at sealevel above sea level is less. 3% less per 1000ft. per pilots book. 55 is max, at sealevel.
the maf is a key sensor on this car,unplug it see if power returns, (but will that is limphome mode and spark advance is was as will be power)

my list from post 1.

why not do signature here,
like this," Suzuki X90, 1996, what transmission?, what drive line? 4wd or 2wd?"

and my red list?
NO TRANSMISSION STATED? 5-speed manual & 4WD
NO SPARK PLUGS STATED (J PLUGS AND gap SETTING at 0.028" not NGK machine set at 0.045" as all are.!)? Plugs are recent, and are J-style gapped at .028"
NO country stated, USA or Canada, the ECU is not the same in both countries, so I must ask country,sorry. The emissions sticker on the hood looks similar to your '96 sticker you posted earlier, so US spec
No new FUEL filter? I have not replaced the fuel filter, but will check with PO if he did
IS TANK FUEL BAD, IS IT OVER 15% FULL, IF NOT DTC do not set for P0300. (ok we know its not below 15% now)
NO outdoor temperature stated. please tell me that. Line 15 of the scanner data shows the inlet air temp which should be close to the outside air temp that day... but with 22 deg. C being almost 72 deg. F, I don't think it was that warm that day.

knowing this we can ignore vast numbers of tests. all wasted.

what is known.
engine is ok, it is not a bad engine,
my guess is injectors will pass the balance test and are not clogged but only based on 'new injectors put in"
the fuel pressure I guess is ok in frame 15, as it MUST BE.
the next is maf , clean it, really this is a 50k mile service point.
if car is driving on a highway fast or on 8 lane freeway,the air that lands on the car is nasty full of oil and crap, and the MAF eats that crap and cokes up.
in town car only not likely.

the maf needs to be cleaned using the can and straw with 8 " inches gap from end of stray to MAF . keep your distance,
and hit it 3 times, 1minute soaks each, time, or more, 5 even if filthy max.
what happens with a dirty MAF
it Under reports air.
and the ECU can not inject fuel correctly with any weak maf, and will bog'
one test it unplug the maf , go to limphome does power wake up, yes, MAF is bad. or just dirty, its just tuneup step on all cars with maf.
some cars have a MAF that self cleans, at key on, I do not think this maf does that. so is a SERVICE POINT or as old guys say TUNE UP step.
in short , weak maf or injectors clogged or low fuel pressure , at frame 15

[fixkick]

so no quasi dyno tests for you , ah , shucks.
I guessing weak maf,


X90 , has its own set of induction parts.
the IAT on our cars is on the air cleaner box. on your car its on right rear side of top air cleaner box, and is the temp inside that box at all times,
the box warms up on any running engine (induction all) via hot air off the radiator, huge air hot. so is only INDUCTION AIR TEMPS.

IAT 22C, but for it to read the outside air, car must be outside , hood up and then for 12 hours, it may read Outdoor temps, (5% accuracy at the best) or +/-10%.
this sensor a tad off will never cause any car to bog. ever. its super fine trim , to correct MAF readings (major readings) is all.

sorry if I mix up posts, so many there are, from others.
I presume the other owner did not put in a new maf? or use crap china maf, (markings on side matter)
and not cleaned yet?
I think the maf is weak. that is what I think now. but, there are other tests.

MAF, is it, if the engine runs ok, (itself) and cat not melted, (engine pumps air ok )
the MAF is weak or the injectors are clogged
but if fuel pressure reads wrong at BOG POINT this is first. we always check this, first if the engine goes lean.

[Fabricator]

more maf bad news. ( all this is like first thing i do on any not new car, bogus parts checks, hacking signs, and parts missing)
this car is old, and was in the hands of others
and if you the old owner bought and put in a C4 CHina cloned MAF< well those are most times, junk >>> example:1 http://fixkick.com/sensors/china-maf/cloned-maf.html

PO states that a local shop tried the MAF swap that did not help - he (PO) did not confirm if the replacement MAF was OEM Suzuki, but assumed that it came from the parts supplier the local repair shop uses. In addition, the PO replaced the fuel filter

the side of you maf has a label
58B00: (< usa maf , in Europe >57b, Air meters non hot wire)
this label; (not C4 brands) is marked with makers name, Misubishi, Hitachis or just suzuki, and this number marking, MAF does have the 58B00 label you describe

today we have far better choices (unlike suzuki $1200 priced tag , ouch)

https://www.rockauto.com/en/catalog/suzu...ensor,5128


some cars are hacked, for sure maf end with cold air mod (malarkey to the max)
the maf is now not mounted at all, or still stock and bounces around like toy. killing the maf dead.
I cant see under your hood for all those things wrong, no can do. No cold air intake kit - all stock airbox installation

[Fabricator]

IAT 22C, but for it to read the outside air, car must be outside , hood up and then for 12 hours, it may read Outdoor temps, (5% accuracy at the best) or +/-10%.
this sensor a tad off will never cause any car to bog. ever. its super fine trim , to correct MAF readings (major readings) is all.

That makes sense for 22 deg. C reading with warm/hot engine - looking at weather for 03 DEC, it said high of 50 deg. F and a low of 41 deg. - I seem to recall it being in low to mid 40's when data collected

[Fabricator]

OK - I took the beast out last week to get more gas and drive it around to see if I could get it to throw a DTC, which it did - a P0300. Unfortunately, the freeze frame data captured by my scanner was a surprise... only 7 of the PIDs show data compared to the amount of PIDs that are available when all are selected in the live data function (see attached file).

Luckily, I was reading live data when the DTC was generated, so when I created the attached .xls/Excel file from the frames of data generated, I plugged the freeze frame data in right before the scanner showed the DTC as being generated. While there are some readings throughout the engine data that look a bit off to me, I don't see anything jumping out at me that caused the P0300 DTC though.

Yesterday afternoon, I pulled the MAF and cleaned it as directed, then tested it using the MAF 13800-58B00 info page. All numbers read looked pretty much normal when back probing wires:

Key on, no start - Blue/Black: .006v; Gray/Black: 1.338v; Engine started, and Gray/Black was 2.069v @ 792 RPM Revving the engine to 3-4 K RPM in neutral showed it going up to just over 3 volts.

Unplugging the MAF and the TPS separately while the engine is misfiring/bogging made no significant difference, but they did generate DTC for being disconnected.

Checking the PO's FSM, I could not find a fuel injector balance test - is that the test where the injectors are removed and tested on the bench to see how much fuel the injectors move over a specified amount of time to see if they are all working the same/within spec?

I forgot to grab my propane bottle setup from our cabin last weekend so I can do some vacuum leak testing, and to send some down the intake when the engine is running poorly.

Will keep working this as weather permits...