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

[fixkick]

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)?

all;  looks good.
"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." a  great test. so the air leak dropped it to 3mS.
proving the O2 wakes up and that ECU is setting rich condition, and is some input to ECU is wrong, and sure MAF is one, cause.

so adding un-metered air causes O2 to wake up.
I agree,.  
check maf carefully,  for correct voltage on output pin key on nostart,  then idle and then  gunned. and trick below ( a crude dyno)
you have 4speed A/T so use it as a dyno for maf readings,
use AT for load, (in drive, voltmeter to Maf output at idel
then hand brake on , choked wheels and foot on the brake pedal, (safe) now stop the throttle hard, 3 seconds max. see if you can get 3 volts or more.
same test as A/T stall test. the clutch will limit RPM to 1500 to 2000 RPM in gear.  this puts a huge load no engine. for short time. (short time to not overheat clutch)
maybe the MAF is offset high?, a rare event, but anything is possible on  hot wire MAF.
try to find tag on MAF that shows this 58B00  ( I ask this because clones do not have this number)
USA pn. 1992 to 98
13800-58B00

good luck to you !!!

[fixkick]

MAF (Brand Most Plus Part number M3389 102015) last number is date sure.
what in the world is this.
?

ahh that is a cloned maf from china, the $22 buck maf.
400 is par par,
try a MAF from USA rebuilder famous, CARDONE. or Spectra premium, (maker of fuel tanks, USA prime) and this.
even $17 sensors on amazon and 25 more.. all dirt cheap from China.
many will run on engine, but not right. not hold closed loop.


https://www.amazon.com/Cardone-74-10033-...i+Sidekick

delco
or beck, Delphi.

most seen here are good all are top brands, but WVE

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

[fixkick]

the ecu has table inside
that correct the non linear nature of the 58B00 MAF
and if not same , I can imagine the ECU going nuts.
The table takes log curve actual and converts it to linear, FLOW. so the math to inject is simple
I have no faith in any china no name brands
a new one was sent to me to test, DOA in shop
opened it up and the PCB inside was wired backwards. I reversed engineered a schematic for fun, (insomnia)

here it is failing
https://fixkick.com/sensors/china-maf/cloned-maf.html

[SidekickTripper]

Hi Fixkick.

My troubles are over!!!! I cann't believe that the poor quality MAF sensor was reading correctly, but was sending bad information to ECM. Intalled New Cardone MAF sensor 74-10033
At Idle now :
Rich Lean status fluctuating Rich/Lean
IAC 10 L/Min
Inj Pulse dropped to 3.2 ms
STFT 128
LTFT 125
HO2S Activated 801mv fluctuating
TPS .86 volts
Trottle angle .0 degrees
Engine Coolant Verified by Infared 181F and 317 OHMs
And the best part it PASSED SMOG !
15mph HC 25 ppm CO% 0.03 NOX 289 ppm
25mph HC 8 ppm CO% 0.08 NOX 105 ppm

Thanks so much. I thought I was going crazy. Experience again prevails!

[fixkick]

wow that is sooooo good to see. CURED, SOLVED

the problem is worse now, I see like 20 fake makers of MAF there,  not good.  even  $17 MAF, 

thanks for the 3.2mS data point !!! USEFUL that.

Happy Thanks Giving to you and all your family.   (revised MPI page PWM)