1994 Sidekick 16v AT 4x4 4dr virgin ECM Ruby's still there

[fixkick]

so yours is near 5Ms and not 2. that is very bad, if true.
5MS is ECU output and if is near there hot idle then you have bad engine sensor readings or bad ECU. (id say sensors)
not bad injector they only do as they are told. (signals)
one other thing is the tech1 does it subtract,  1ms from PW to show true injection rate?  seem it should to me.  my guess is not.
so 4.8mS is really 3.8mS true injection time. and is 120% too high.

here is my attempt. min open time is dead time (inertia)

my best  try.  if true , your  ECU is injecting crazy high fuel, not just rich.  270% or 2.7 times too much fuel,  the sensors read wrong.
1.8x 2.7 = 4.86ms
assume tech one is not fibbing, and is on ECT we do not know if tech1 sees real Injector PW or uses a table based on ECT readings and maf.(IDK)
this is why real scopes are a winner (no lies) and can see the true dead time and true injection rates, no lies.


now TBI (one Injector G16) my real scope is drew this, for better way to comment on PWM.
see 1.4Ms here. hot idle,
0.7mS dead time (inertia of pintle)
see the modulation it does to not overhear the tiny coil.
that is no load Acceleration not in gear, and no hills.  just hand gunned throttle.
dead time is when injector can not inject fuel at all. (from 0v to 12vdc time zero) fuel flows at the first left small "c"

[fixkick]

i'd want to check o2 carefully.
the old sidekicks made before 1996 (OBD2, USA)
love to go too rich, for many reasons, later the OBD2 ended gross error. (smarter it is, by design)
The limphome mode is horrible then pre 96 we know that and is a dead sensor and yours are not 100% dead.

The O2 is tricky here, this ECU is not smart like modern cars that see a lazy O2, or one that sticks. OBD1 not reliable at all.
Modern cars do (fancy NON Congruent tests) eg: maf shows high flow , TPS none, (means one is fibbing like my new JEEP does)
The code for stuck o2 on this are is not smart nor reliable to trust.

The top cause (code 12 flashing CEL even driving car wild and code 12 flashing (hint hint)
the O2 and MAF are both suspected, for sure MAF made in china from SOME TING WONG., they suck. and invites guessing parts and now have 2 or more problems in EFI not just 1. guessing and buying dirt cheap parts from china is fail max point.
The O2 best is BOSCH (NGK) and with heater and listed as G16b fit. see my hard to buy parts page on O2.
the O2 has 3 or 4 wires never 1, never 2 this year ok?
The heater 02 must be good, some of these cars have relay that runs the O2 heater and those fail and ECU is oblivious to that fact.
in 1996 the heater is fully monitored,, DTC errors for dead heater do not lie.
but on this car, we test it. make sure it is not an open heater.
the O2 will never work with exhaust cracks or header gaskets bad, ever, no car will even 2020.
Cracks sick air
each exhaust PUTT is a pressure wave then goes to vacuum, yes it does and sucks air if cracked. never let it suck air and the 02 works great for 100,000 miles or more.

fuel pressure right
injectors only for this exact engine not china crap (no name ) no name means just that you can not pronounce their name bingo,
leakdown test passes (yours) as must injector balance test pre FSM.
fuel pressure at spec. 31 idle is ok. (its range stated in FSM and on my pump page)
all sensors working correctly (maf , o2 and etc)
no exhaust cracks near 02 sensor. from cat up no cracks allowed. nor bad or missing collector header gaskets.
if air hits O2 the 02 goes to zero volts and 1995 goes MAX HORRIBLE RICH. 1996 USA far less rich, for sure. pre 96 love to go way too rich, OBD1 pain.

the hard part of the 02 is air can get sucked in at odd driving times, not just parked in drive way, engine gets hotter up hills and vibration and engine leans under load, yes leans on the mounts, think about that and now hard it is to find that, not.

[SidekickTripper]

Thanks again,

I have since checked Ohms on all injector coils.
1. 13.8 ohm
2. 13.7 ohm
3. 13.8 ohm
4. 13.8 ohm
engine cold
and monitored the HO2 Idle .874mv operating temp
1000 rpm .869 mv
1500 rpm .874 mv
running for 10 min later
Status Lean
IAC 17 l/min
SPK 7-8 drgrees
INJ PW 4.8
STFT 128
LTFT 117
HO2 .73 mv Deactivated

TPS .86
MASS 2.5
______
10 Min More Idling
HO2 8.74 mv
Activated
Status Rich
_______
10 Min
1740 RPM
Status Lean
IAC 29 L/Min
SPK 34 Deg
PW 4.3 ms
STFT 128
STFT 128
HO2 .49 mv deactivated

I will check partially heated injectors Ohms and check for crack at # 4 exhaust manifold.
with the new information you provided 4.0 ms Idle is not normal.
A crack mainfold upstream would show bias lean all time and low volts correct?
and command rich possibly increasing Pulse Width?
Thanks again keep you posted

[SidekickTripper]

Update

I have had tested and had the injectors cleaned and rebuilt. and I found what appeared to be a small 3 inch long hair line crack at number 4 exhaust port upstream to the 02 sensor. Repaired it and tested with propane for leaks and etc.
Skiping some readings: Normal.
Idle 788
IAC 27 L/Min
SPk Adv 5-12
Inj Pulse Width 4.216
Rich Lean Status: Lean
EGR Temp 144F
ST 128
LT 128
HO2 59 mv 10 Min later 83Mv
Deactivated? (I Not sure what this mean) Closed Loop?
TPS .86 volts
T angle .0
ECT 147F ( error Tech 1) 182F
MAF 2.3

Vehicle failed as a gross polluter
Calif.
15MPH [%C02 10.2] [ O2% 0.0] [HC 502 ppm] [CO 7.01%] [ NOX 95ppm]
25mph [%C02 10.4] [ O2% 0.0] [HC 475 ppm] [CO 6.80%] [ NOX 145ppm]
Help!!!! Is there possible a ECM problem with Injectors Pulse?

[fixkick]

Update (thanks for sharing this )!

I have had tested and had the injectors cleaned and rebuilt. and I found what appeared to be a small 3 inch long hair line crack at number 4 exhaust port upstream to the 02 sensor. Repaired it and tested with propane for leaks and etc. 
Skipping some readings: Normal.
Idle 788
IAC 27 L/Min
SPk Adv 5-12
Inj Pulse Width 4.216
Rich Lean Status: Lean
EGR Temp 144F
ST 128 (I think both trims are lies here, if the 02 goes offline these stick to useless DEFAULTS) 128 is center and default. a silly thing for suzuki to do (0 be better )
LT 128 (lies)
HO2 59 mv 10 Min later 83Mv  (seems stuck low) it must swing not stick low. (only real scope can see what it  really is doing)
Deactivated?  (Im Not sure what this mean) Closed Loop? NO that means the O2 is dead, ECu sees it stuck low. and make eCu go rich. (means open loop)
TPS .86 volts
T angle .0
ECT 147F ( error Tech 1) 182F  (is it 300ohms hot?, if yes scan tool lies, but we know some do... yes)
MAF 2.3

Vehicle failed as a gross polluter  (it sure is) 4 gas and not 5 gas so 02%=0.0 is bogus )
Calif.
15MPH [%C02 10.2] [ O2% 0.0] [HC 502 ppm] [CO 7.01%] [ NOX  95ppm]
25mph [%C02 10.4] [ O2% 0.0] [HC 475 ppm] [CO 6.80%] [ NOX  145ppm]
Help!!!!  Is there possible a ECM problem with Injectors  Pulse?  NO the 02 sensor is dead, only why is  in question.

anything is possible.
ok   HC is high, co is high. (here is one barely passing) as you can see, using this real report (full) your HC is 5 times normal and NOX off the map high.
maybe just a bad CAT?  no,  but a new cat can hide a bad engine for short time as it glows red hot. (not advocating this,... me.)
There can be no air leaks in the exhaust manifold headers at all, zero air leaks. (means gaskets too) and cracked cat header pipe too.

example ,just passing by chin hairs.  (the AVE is data for vast sidekicks state tested)




causes, bad O2, sensor, wrong sensor, wired wrong, or heater in sensor dead, or wired wrong, or the power to the heater is failing.
some cars made these years had a o2, relay that is bad.
seen here. omg I have the drawing still  the wire colors give away the relays job,  pink for sure and blue-black.   all you do is check for 12vdc to pin 3. below.
this is heater power the 02 cell is pin 2.  (The ecu can not see the heater dead) can not. and is only found dead by wise mechanics.



I am not sure if the calif car or fed car gets this class so sensor, heater.

in a shop, most techs, see O2 dead, and gross rich cause an air leak (vacuum) to add air to the induction air path to case lean and monitor the o2 to see if
it wakes up, if not , this is the path to cause and cures, no others.
 
I buy Bosch sensor, for these reasons, well they are good and have all versions per my complex chart. as you see getting the wrong one is so easy.


Just added to Image gallery above.  the green comments are mine for sure showing wire count and are not part of any P/n

[fixkick]

the O2 evolved fast on this car, from 1 wire to 4, making this so hard to get right.
what O2 do you have,? is the harness 3 wire or 4? this is what matters not the sensor ,ignore it for now, just the 02 harness jack pin count wired.
does the under hood suzuki white large sticker have the word California on it? (if yes it is true calif car)

https://fixkick.com/sensors/OxyGen_senso...replace_it

[fixkick]

if the 02 sticks low on all these pre 96 cars it goes hugely rich, unlike most cars on earth. super rich, punishment mode then.
the heater must get 12vdc to it. that is first. at idle, or even key on. I think.
The smog brain inside want it hot as fast and as soon as possible. (so the 02 can wake up fast and soon)

[SidekickTripper]

Hello Again,
Since last post I have decided to change the 02 sensor to Bosch 13073-4. My Sidekick is a Calf. Federal Emissions label states Calif. it has 4 wires and the EGR has a temp sensor.

There must have been a problem with the 02 sensor because now the vehicle goes in to closed loop fine it's rich lean status is now rich. Go figure it changed and the pulse width drop slightly but is still above 4 ms. The O2 sensor stay roughly about .925 mv Maybe The hairline crack repair fixed the bias lean and or the 02 change.

I did not check the new Bosch sensor before installing it, but I am getting 12 volts at BLK/WHT and will check again for heated O2 circuit.

I disconnected the vacuum hose from purge solenoid causing a vacuum leak and the HO2 sensor went to varing mv about 10mv to 900mv . The Injector pulse width drop to about 3 ms +or - Lean Rich status fluctuating between both.


I going to start over and check all system and circuits again with a DVOM.
I will use the sensor and actuator testing guide that you have posted and compare them to the Tech 1
I already know that the ECT wont be accurate.

The funny thing is the vehicle is idling great it accelerates great and has a lot of power, but it is running extremely rich.
Also I looked a the ECM the sticker says 33920-70EA0 , E2T42971 T1, 4712B A4, US-MT and in my opinion looks like a rebuild. Capacitor has an X on it and it looks very clean.

Back to square one...
Keep you posted.

[fixkick]

Hello Again,
Since last post I have decided to change the 02 sensor to Bosch 13073-4. My Sidekick is a Calf.  Federal Emissions label states Calif. it has 4 wires and the EGR has a temp sensor.

There must have been a problem with the 02 sensor because now the vehicle goes in to closed loop fine it's rich lean status is now rich. Go figure it changed and the pulse width drop slightly but is still above 4 ms. The O2 sensor stay roughly about .925 mv Maybe The hairline crack repair fixed the bias lean and or the 02 change. 

I did not check the new Bosch sensor before installing it, but I am getting 12 volts at BLK/WHT  and will check again for heated O2 circuit.

I disconnected the vacuum hose from purge solenoid  causing a vacuum leak and the HO2 sensor went to varing mv about 10mv to 900mv . The Injector pulse width drop to about 3 ms +or - Lean Rich status  fluctuating between both.


I going to start over and check all system and circuits again with a DVOM.
I will use the sensor and actuator testing guide that you have posted and compare them to the Tech 1
I already know that the ECT wont be accurate.

The funny thing is the vehicle is idling great it accelerates great and has a lot of power, but it is running extremely rich.
Also I looked a the ECM  the sticker says 33920-70EA0 , E2T42971 T1,  4712B A4,  US-MT and in my opinion looks like a rebuild. Capacitor has an X on it and it looks very clean.

Back to square one...
Keep you posted.

that is so true, the lean burn (EPA spec) makes low smog not max power, only rich makes max power, like in WOT mode goes rich and O2 shuts off then.
pwr is max power
mpg is max mpg.
O2 holds at Stoich, (cleanest)
A new o2 my do the trick, can be had cheap if shop around.
A 02 MY BE POISONED BY odd things, (snake oil,  or coolant leaks) best is clean fuel, and clear normal oil in the pan.)
some times a rAD leak down test finds marginal leak coolant to combustion chamber, but careful spark plug tip viewing can save the day here.

[SidekickTripper]

Update:
Vehicle temp ECT sensor verified 180 317 ohms
MAF (Brand Most Plus Part number M3389 102015)
Koeo:
Bl/Blk 12.57 VDC (Battery voltage)
Blk .02 VDC
Gry 1.64 VDC
Running:
1.96 VDC 800 RPM
volts rise with acceleration
ISC 14.2 ohms at operating temp
Pinched fresh air hose dies immediately, starts pinched then idles at approx 500rpm
TPS: .84 volts idle and throttle swing to 4.28 volts

Tech 1
Rich/Lean : Rich
IAC Air Flow: 28 L/Min
IAC Adjust Monitor :0%
Spark Advance: varies 5-12 degress
Injector Pulse width: 4.320
STFT 128
LTFT 128
HO2 903 MV not varying
O2S Activation Activated (Closed loop)
TPS: .84 VOLTS
Throttle Angle: .0 degrees
ECT reads 145F ( verified 180F infraed and 317 Ohms, reading again)
MAF 2.3 g/s

Injectors have been cleaned and rebuild and tested. I have a report showing results:
Inj # 1 170 CC/Min
InJ # 2 171 CC/Min
Inj # 3 170 CC/Min
Inj #4 160 CC/Min
SYS Balance 1.2 %
Total Sys LBS/Hr Static 64.76
CC fuel/Min H.P. Static 7.16
BSFC/ @ 80%/@EST. H.P. 0.55
Duty Cycle at Est. B.H.P. 0.73
@BSFC of .65 : 79.7
@BSFS of .55: 94.2
@BSFC of .50: 103.6

I will be changing the oil again for the 3rd time in case of fuel saturation and will be removing spark plugs for inspection as suggested and I will perform a block test for combustion gases.

As I mentioned before: I disconnected the vacuum hose from purge solenoid causing a vacuum leak and the HO2 sensor went to varing mv about 10mv to 900mv . The Injector pulse width drop to about 3 ms +or - Lean Rich status fluctuating between both.

My thoughts on this is that I created UN-metered ahead of the IAC and MAF sensor. Is it possible either the IAC is only opening 50% because when I pinched it it died and didn't go to 400 rpm and or a Bad MAF sensor( Poor quality)?