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Dash Tacho Wire A1
#1
Hello. 1992 tracker 8 valve tbi 2 door 4wd 5 speed
Still investigating odd surges while cranking (starts at 3000rpm then falls down to 400rpm, then back up, then motor dies). 
The fuel injector was previsouly hot wired to stick open. I removed the hot wire and now I get this issue. 
I checked the injector resistance (looked good), replaced coil and igniter, still no fix. 


Question about the brown wire going from the noise supressor to the tach and ECU: 
For the ECU to properly pulse injector, does the brown wire need to be connected to the instrument cluster as well as A1 on ECU? 
Basically - if I remove the entire instrument cluster, should the ECU still properly pulse the injector? I'm worried that hte connection on my cluster is messed up and I want to test the wire by just routing a whole new wire from the supressor to pin A1 to see if this resolved the issue. 

If not, I might need a new ECU. (G103 ground went to alternator, not starter, so it may be burnt). 

In additon I also routed an extra 6 gauge (awg) wire from ground G100 to alternator.
Reply
#2
(10-27-2021, 11:18 AM)sina27 Wrote: Hello. 1992 tracker 8 valve tbi 2 door 4wd 5 speed
Still investigating odd surges while (after) cranking (starts at 3000rpm then falls down to 400rpm, then back up, then motor dies).   400 is stuck open EGR valve most times.
The fuel injector was previously hot wired to stick open. I removed the hot wire and now I get this issue.  (hot wiree to what?)
I checked the injector resistance (looked good  1 ohm it is. ), replaced coil and igniter, still no fix.  (ok ,  bad wiring,  (41 is real but is wire caused, opens or short on all things it goes t0)
99.9% of the time no ECU ever blows up inputs ever, it has super good protection on all INPUTS, outputs love to blow up for sure 2 wire TBI injectors.




Question about the brown wire going from the noise supressor to the tach and ECU: 
For the ECU to properly pulse injector, does the brown wire need to be connected to the instrument cluster as well as A1 on ECU? 
Basically - if I remove the entire instrument cluster, should the ECU still properly pulse the injector? 
Removing the cluster never ever rumors A1 signals to the ECU. (the wire is T junction mid harnees) cluster and ECU and cruise controller.
but if the speed tacho meter shorts A1 then fuel is cut.  nothing must ever short out or cut the A1 brown were,  cluster pulls do not cut A1.

I'm worried that hte connection on my cluster is messed up and I want to test the wire by just routing a whole new wire from the suppressor to pin A1 to see if this resolved the issue. 

If not, I might need a new ECU. (G103 ground went to alternator, not starter, so it may be burnt).  that is not good that, , it can burn that wire up. (depends on what was there actually)

In additon I also routed an extra 6 gauge (awg) wire from ground G100 to alternator. (good , rusty alternator love better grounds)
so you start a new post every time?  I don't care but is odd. that, so I can read the posts as one and understand it all.
that hot wired injector is super bad.
there are 2 injector drivers in the ECU on on hot side and one on the ground side. (unlike any other car made,  nor 16v = mpi x4 drivers not 8) 8v suzukio's only.
both lines must pulse or the injector will fail,  dead or be super wildly rich over injecting
wish I knew about hotwire  first.  this is common seen (bad acts) on 8v the ecu burns out the injector driver (dead open and dead or is shorted this driver.) 
So the owner goes WILD with hot wire ideas all of which are 100% hopeless. (do not hot wire injectors, hook them up correctly to a good ECU)
the truth is one can scope both wires on the injector to see the waveform or us a NOID light in a tricky way. (I will tell this last)
if A1 spark readback is cut,  the ECU see that and cuts all fuel but if the wild man above hotwired the injector well that BYPASSES the A1 spark failure  test and fuel  cut.

the tacho pin brown wire prevents as seen on TV crash and burn, that is it's #1 most importnant job that fuel cut.
code 41 can be for intermittency in A1 or dead A1 ,  1 is 10 misifires is code 41, so is dead A1. same code 41.

a noid lamp test, smaller is better and incandescent best, not LED.


The Noids lite test is say.
the 2 injector  wires can be 3tested 3 ways and 3 ways best.

the test is with injector not connected
a cranking tests and with no fueling can not start and is  safe for you,  wheels chocked. in neutral and hand brake set hard.
https://fixkick.com/INJECTORS/NOID101.html#TBI

that first test is NOID lamp on the 2 colored wire pins to the harness of course. red and yellow pins
just for fun see my cope on those 2 pins. (2 pin transverse mode tested as the injector sees it is this.test.1
https://www.fixkick.com/INJECTORS/INJ-red-to-yel-w1.jpg
the noid  just  flashes. cranked slow. must not stick on but must flash, all tests must flash or the DRIVER RED OR YELLOW are bad. stuck on is bad.

test 2 is from red pin to ground (red is the +12vdc driver transistor pin.)
noid to pin red and other noid pin to engine ground. it must flash
now the tricky #3 tests

#3 is the ground driver test.
I use  jumper wire with 2amp inline fuse holder from Battery + lug, and othere end of wire fuse to the NOIP 2nd pin
NOID 1st pin to the yellow injector PIN.
key on crank and it must flash if stuck on it has bad transistor in the ECU and easy to replace really/'

if EITHER PIN YELLOW OR RED DO NOT FLASH THERE WILL BE NO FUELING AT ALL (Thus why folks hot wire them)
if EITHER same 2 pins are stuck on (glows) full time and do not flash, that causes HUGE RICH mixtures and is a bad transistor it only a shorted bad transistor. easy to replace.

do not hot wire either pin to battery directly with copper wire only, + or  you will blow up the transistor for sure the yellow.



here is the full set of tests (ignore g10 and metro examples ,just G16 TBI 8v)

https://fixkick.com/INJECTORS/the-pulses-matter.html

before the car and run right both Q101 and Q102  must both work and both must pulse. 91 to 95 are all the same , this circuit and was discovered by me.  fixing bad ECU.
also R225 can burn open making yellow dead too. uP is micro processor + port expanded. These 2 big transistors are easy to find. new. standard Japan made and number common.
My best Theory here is there are 2 transistors so I one shorts, the INJEcTOR is not burned up to hell as it would..  (a great idea really)
[Image: injector-drivers.jpg]
http://www.fixkick.com
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#3
a 12v to 16vdc lamp works ( LED might work but really is too sensitive)
20MA is best not 1 amp,but way less.
is best, that way leaking transistors can be seen to fail.

https://fixkick.com/NOID/91-noid-sf1.jpg

one good lamp is cluster idiot lamp or back ground lamp using in the speed cluster wired up as noid lamp with 2 clips .
a ge194 lamp seen in walmart may work good. 0.25amps 3watt , lower watts is best for testing but no too low as LED are.
transistor can be good or bad and bad 3 ways shorted , open or leaking. (I always not to find all 3 including leaking) glows dim and wrongly that.
http://www.fixkick.com
Reply
#4
Thanks Kick!
Still waiting for the ECU replacement to arrive - but I may have made some headway using the ECU I already have.
 I did a bunch of the ECU voltage tests and continuity tests. I of course removed the red fuel injector hot wire, so eveything is wired as it should be. 
With key in on position I'm getting over 12 volts to power source pins (B7 for example). 
The brown tach wire gave me over 11 volts so I guess it meets spec. I still might want to route a new brown wire just as a test. 
Resistance test for fuel injector between red and yellow wire gave me 1.5 ohms, within spec (at ECU terminal B8 and B17). 

What I did next: I removed the TBI cover so I can take a look at the injector. I cleaned everything with carb cleaner too. 

I started the motor and it was running, 2000rpm I think. The injector seemed to pulse and spray correctly in a cone like matter. After 30 seconds or so the idle started coming back down, and then I noticed the fuel injector was "misfiring", as if it would only intermittently inject. It did this until the motor died. Sometimes I would give it gas which would rescue the injections, but when back down to idle it looked like the injector was "misfiring". 

One note: I feel that my FPR works fine because I dont see gas dribbling from the vacuume hose.  Have yet to do the real test using a pressure tester. 

Can improper EGR vacumming cause any of these symptoms? 
I noticed one of the metal nipples on my EGR valve (the one that connects to the EGR modulator via the thicker vacuum hose) is broken off. Could this be causing the car to stumble and die?
Reply
#5
had some luck. 
replaced brown wire and it seems to idle. also, IAC wire was bad so I fixed it an now it idles. Not getting any DTC codes. 

However its running very very rich:
The car has no CAT, and hole in pipe right before muffler. 
Also th EGR bark nipple is broken off.
I assume with no backpressure the EGR system isnt working properly which could be giving me this rich situation.

Think the lack of CAT and subsequent EGR issue is throwing my car into failsafe mode making it run rich?
I'm not getting code 41 anymore, but its still  rich and smokey. Compression is also 150 cold so dont think its rings.
Reply
#6
(10-29-2021, 09:05 AM)sina27 Wrote: had some luck. 
replaced brown wire and it seems to idle. also, IAC wire was bad so I fixed it an now it idles. Not getting any DTC codes. 

However its running very very rich:
The car has no CAT, and hole in pipe right before muffler. 
Also th EGR bark nipple is broken off.
I assume with no backpressure the EGR system isnt working properly which could be giving me this rich situation.

Think the lack of CAT and subsequent EGR issue is throwing my car into failsafe mode making it run rich?
I'm not getting code 41 anymore, but its still  rich and smokey. Compression is also 150 cold so dont think its rings.
injector misfiring is super bad,  the ECU is doing that and is wrong, only why  matters
the EGR is dead now both ways, no CAT and no bark tube, means EGR will never ever open again, and must be closed now and if is closed not cause rich fueling
after all the EGR is never used EVER at  IDLE nor is it used at WOT wide open throttle. SO those are not rich even on day1 new car. EGR is for cruising and NOX reduction only.
but if  the  injectors misfires the ECU  will go mad due to huge vacuum fluctuations at the Map SENSOR.
are your ECU caps good, if not the injector will misfire so will spark or as we know all code 41s is spark misfire and 41s cut fuel  at the injector, so that 41s would  cause the injector to cut fast.
if 41s, 42s are gone the injector must not misfire,  or CAps IN ecu ARE BAD. (NO CMP ERRORS CAM SENSOR IN DISTRIB.)

150 IS GOOD PRESSURE, COLD OR WARM ENGINE,

So what causes smoke black if no DTC errors and not  in limphome mode.
in order.
1:way too high fuel pressure, saw one old care that had a siillly huge fuel pump outiside  the tank off a FORD Crown Victoria, and it was so powerful it over loaded the  FPR all the time
like garden hose to a  fire Hydrant, wild..

2: gross misfiring,
3: map sensor reads wrong key on no start and key on idle voltage out, of MAP seen on my map table , see map page in fixkick.com type map there.
4: vacuum is wrong 19inches HG. at idle and steady not bouncing like mad. ever and for sure not while idling at 800rpm ISC working and controlling idle hot engine.

5:
The ECU may need new CAPS (called a ReCAP job) everyone Ive seen needed, a simple job if old school soldering is easy for or others.
engine not at 180f coolant,
6:
ECT not at 300 ohms hot but way higher ohm ,the ECU adds lots of fuel (too much for any hot engine)
http://www.fixkick.com
Reply
#7
(11-06-2021, 04:49 AM)fixkick Wrote:
(10-29-2021, 09:05 AM)sina27 Wrote: had some luck. 
replaced brown wire and it seems to idle. also, IAC wire was bad so I fixed it an now it idles. Not getting any DTC codes. 

However its running very very rich:
The car has no CAT, and hole in pipe right before muffler. 
Also th EGR bark nipple is broken off.
I assume with no backpressure the EGR system isnt working properly which could be giving me this rich situation.

Think the lack of CAT and subsequent EGR issue is throwing my car into failsafe mode making it run rich?
I'm not getting code 41 anymore, but its still  rich and smokey. Compression is also 150 cold so dont think its rings.
injector misfiring is super bad,  the ECU is doing that and is wrong, only why  matters
the EGR is dead now both ways, no CAT and no bark tube, means EGR will never ever open again, and must be closed now and if is closed not cause rich fueling
after all the EGR is never used EVER at  IDLE nor is it used at WOT wide open throttle. SO those are not rich even on day1 new car. EGR is for cruising and NOX reduction only.
but if  the  injectors misfires the ECU  will go mad due to huge vacuum fluctuations at the Map SENSOR.
are your ECU caps good, if not the injector will misfire so will spark or as we know all code 41s is spark misfire and 41s cut fuel  at the injector, so that 41s would  cause the injector to cut fast.
if 41s, 42s are gone the injector must not misfire,  or CAps IN ecu ARE BAD. (NO CMP ERRORS CAM SENSOR IN DISTRIB.)

150 IS GOOD PRESSURE, COLD OR WARM ENGINE,

So what causes smoke black if no DTC errors and not  in limphome mode.
in order.
1:way too high fuel pressure, saw one old care that had a siillly huge fuel pump outiside  the tank off a FORD Crown Victoria, and it was so powerful it over loaded the  FPR all the time
like garden hose to a  fire Hydrant, wild..

2: gross misfiring,
3: map sensor reads wrong key on no start and key on idle voltage out, of MAP seen on my map table , see map page in fixkick.com type map there.
4: vacuum is wrong 19inches HG. at idle and steady not bouncing like mad. ever and for sure not while idling at 800rpm ISC working and controlling idle hot engine.

5:
The ECU may need new CAPS (called a ReCAP job) everyone Ive seen needed, a simple job if old school soldering is easy for or others.
engine not at 180f coolant,
6:
ECT not at 300 ohms hot but way higher ohm ,the ECU adds lots of fuel (too much for any hot engine)

T
hanks Kick. I put in another ECU, new injector o rings, new FPR. The injector is firing pretty well. NO DLC CODES. 
Im getting closer to finding the culprit - so my cold idle was very high and it was surging, then when warm it idled back down and then the rich symptoms started. While running, I unplugged the ISC harness, and then it seemed to idle better - and NO MORE SMOKE. 
The resistance of the ISC is 12.3 ohms and the voltage is withing range.
 The ISC looks new. I tried adjusting the air bleed screw on the throttle body as well as the adjustment screw on the ISC valve. I was able to get the idle down, no more surging, but its still running a tad rich. For the ISC adjustment screw, I turned in CCW, then blew air into it while turning it CW until I could barely blow air into it, then just half a turn more CW.  I think it was turned out CCW too much which is why it was surging so much which is why it doesnt surge anymore. 
For the TB air bleed screw - I turned it in clockwise all the way, and then half a turn out until hot idle is set at 800rpm. Now what happens is: 
  • When cold, it idles at 2500rpm, then it takes about 5 minutes of driving to slowly come down to 1000rpm
  • After 15 min of driving it fall even lower now, about 500rpm - so if I just the TB air bleed screw to adjust it now to 800rpm, I think when cold it will idle way too high now. So cold is too high of rpm, and stays high for too long if hot is 800rpm. 
My plans: I ordered the TB throttle body gasket kit from Rockauto. I will be removing the throttle body and then cleaning the IAC and ISC ports and the TB air bleed port with carb cleaner. I will replace the base gasket using the correct "91+" in the set which you have photos for. While the throttle body is off, I will also re-calibrate TPS. I will then do a rough ISC calibration using the method you described where I turn the screw CW until the valve just seats (very minimal air flow) and then a half turn more. I will then re attach everything and then adjust the TB air bleed screw until fully hot idle is 800rpm. 

My stat and stat gasket and ECT sensor is new so that shouldnt be the problem. 
One side question: I did install a new radiator cap. The imprint says "0.9" which I assume is 13 PSI. My 96 16 valve kick has a "1.1" 16PSI cap. Do you think the pressure rating on the cap is too low? 

Thank You
Sina
Reply
#8
(11-09-2021, 05:08 AM)sina27 Wrote:
(11-06-2021, 04:49 AM)fixkick Wrote:
(10-29-2021, 09:05 AM)sina27 Wrote: had some luck. 
replaced brown wire and it seems to idle. also, IAC wire was bad so I fixed it an now it idles. Not getting any DTC codes. 

However its running very very rich:
The car has no CAT, and hole in pipe right before muffler. 
Also th EGR bark nipple is broken off.
I assume with no backpressure the EGR system isnt working properly which could be giving me this rich situation.

Think the lack of CAT and subsequent EGR issue is throwing my car into failsafe mode making it run rich?
I'm not getting code 41 anymore, but its still  rich and smokey. Compression is also 150 cold so dont think its rings.
injector misfiring is super bad,  the ECU is doing that and is wrong, only why  matters
the EGR is dead now both ways, no CAT and no bark tube, means EGR will never ever open again, and must be closed now and if is closed not cause rich fueling
after all the EGR is never used EVER at  IDLE nor is it used at WOT wide open throttle. SO those are not rich even on day1 new car. EGR is for cruising and NOX reduction only.
but if  the  injectors misfires the ECU  will go mad due to huge vacuum fluctuations at the Map SENSOR.
are your ECU caps good, if not the injector will misfire so will spark or as we know all code 41s is spark misfire and 41s cut fuel  at the injector, so that 41s would  cause the injector to cut fast.
if 41s, 42s are gone the injector must not misfire,  or CAps IN ecu ARE BAD. (NO CMP ERRORS CAM SENSOR IN DISTRIB.)

150 IS GOOD PRESSURE, COLD OR WARM ENGINE,

So what causes smoke black if no DTC errors and not  in limphome mode.
in order.
1:way too high fuel pressure, saw one old care that had a siillly huge fuel pump outiside  the tank off a FORD Crown Victoria, and it was so powerful it over loaded the  FPR all the time
like garden hose to a  fire Hydrant, wild..

2: gross misfiring,
3: map sensor reads wrong key on no start and key on idle voltage out, of MAP seen on my map table , see map page in fixkick.com type map there.
4: vacuum is wrong 19inches HG. at idle and steady not bouncing like mad. ever and for sure not while idling at 800rpm ISC working and controlling idle hot engine.

5:
The ECU may need new CAPS (called a ReCAP job) everyone Ive seen needed, a simple job if old school soldering is easy for or others.
engine not at 180f coolant,
6:
ECT not at 300 ohms hot but way higher ohm ,the ECU adds lots of fuel (too much for any hot engine)

T
hanks Kick. I put in another ECU, new injector o rings, new FPR. The injector is firing pretty well. NO DLC CODES. 
Im getting closer to finding the culprit - so my cold idle was very high and it was surging, then when warm it idled back down and then the rich symptoms started. While running, I unplugged the ISC harness, and then it seemed to idle better - and NO MORE SMOKE.  GREAT news !
The resistance of the ISC is 12.3 ohms and the voltage is withing range. good and voltage will be 1/2 of alternator/battery voltage, or 7vdc using only analog needle voltmeter (if not turn the bleed screw (hot engine) to 7vdc on the needle.
 The ISC looks new.
 I tried adjusting the air bleed screw on the throttle body as well as the adjustment screw on the ISC valve. 


I was able to get the idle down, no more surging, but its still running a tad rich.
ISC 5mm hex screw is factory set, but can be set to just lightly closed , just landing there to the seat inside.
For the ISC adjustment screw, I turned in CCW, then blew air into it while turning it CW until I could barely blow air into it, then just half a turn more CW.  I think it was turned out CCW too much which is why it was surging so much which is why it doesnt surge anymore. 
surging is the ECU doing that to the ISC< due to 800 RPM can not be attained, (ECU + ISC servo actions that)
in fact all air leaks in to the plenum can cause surging if 800 can not be attained, ECU controls that. only. at IAC. hot engine, cold is iAC controls all thermal.


For the TB air bleed screw - I turned it in clockwise all the way, and then half a turn out until hot idle is set at 800rpm. Now what happens is: 
  • When cold, it idles at 2500rpm, then it takes about 5 minutes of driving to slowly come down to 1000rpm
  • After 15 min of driving it fall even lower now, about 500rpm - so if I just the TB air bleed screw to adjust it now to 800rpm, I think when cold it will idle way too high now. So cold is too high of rpm, and stays high for too long if hot is 800rpm.   (the IAC is 100% thermal and the RPM is based on water temps the colder water is the higher cold RPM is all by the actions of the IAC WAX PELLET INSIDE, IT.
My plans: I ordered the TB throttle body gasket kit from Rockauto. I will be removing the throttle body and then cleaning the IAC and ISC ports and the TB air bleed port with carb cleaner. I will replace the base gasket using the correct "91+" in the set which you have photos for.  THIS IS A GREAT IDEA  AND THE BOTTOM GASKET MUST BLOCK THOSE 5 Tiny holes.
While the throttle body is off, I will also re-calibrate TPS. that is the best way and TV set to 0.0005" butterfly gap to 99.9% closed, FIRST (TV stop screw inspection first )
I will then do a rough ISC calibration    using the method you described where I turn the screw CW until the valve just seats (very minimal air flow) and then a half turn more. I will then re attach everything and then adjust the TB air bleed screw until fully hot idle is 800rpm. 
and ISC set to 7vdc, use a voltmeter, with real needle, even a $10 meter like that at walmart.  this needle tick averages the 200 Hz square wave signal on the ISC pins. 7vdc is it.

My stat and stat gasket and ECT sensor is new so that shouldnt be the problem. 
One side question: I did install a new radiator cap. The imprint says "0.9" (0.9 bar is 90% of 14.7 psi atmospheric pressure ) and is spec.
which I assume is 13 PSI.
My 96 16 valve kick has a "1.1" 16PSI cap. Do you think the pressure rating on the cap is too low?   no the difference is marginal. and the cap is crude, it is only a ball park number.


Thank You
Sina


yes get a needle analog meter like this. volts DC.


https://www.walmart.com/ip/DC-AC-1000V-V...hbdg=L1700


hot engine, 180f water
connect meter to ISC wire pair.
battery is at 14.7 or 13.3vdc (the lower number is float charge , higher number is fast charging, divide by 2.
7vdc is good goal at ISC (use the 10vdc scale or if your meter is 20vdc use that) DC. not AC.
turn the bleed down until it reaches 7vdc,  and that is now 50% duty cycle and even at high altitude the ISC works. right.  and 800 RPM held solid.

do this all after fiddling with 6mm hex screw on isc, set it for just lightly closed engine off. just kissing the rubber ringed seat inside.
if the  seat leaks a bet that is ok the bleed screw will correct that error easy.

btw your doing GREAT !
good luck to you and your little Sidekick.
http://www.fixkick.com
Reply
#9
(11-11-2021, 04:57 AM)fixkick Wrote:
(11-09-2021, 05:08 AM)sina27 Wrote:
(11-06-2021, 04:49 AM)fixkick Wrote:
(10-29-2021, 09:05 AM)sina27 Wrote: had some luck. 
replaced brown wire and it seems to idle. also, IAC wire was bad so I fixed it an now it idles. Not getting any DTC codes. 

However its running very very rich:
The car has no CAT, and hole in pipe right before muffler. 
Also th EGR bark nipple is broken off.
I assume with no backpressure the EGR system isnt working properly which could be giving me this rich situation.

Think the lack of CAT and subsequent EGR issue is throwing my car into failsafe mode making it run rich?
I'm not getting code 41 anymore, but its still  rich and smokey. Compression is also 150 cold so dont think its rings.
injector misfiring is super bad,  the ECU is doing that and is wrong, only why  matters
the EGR is dead now both ways, no CAT and no bark tube, means EGR will never ever open again, and must be closed now and if is closed not cause rich fueling
after all the EGR is never used EVER at  IDLE nor is it used at WOT wide open throttle. SO those are not rich even on day1 new car. EGR is for cruising and NOX reduction only.
but if  the  injectors misfires the ECU  will go mad due to huge vacuum fluctuations at the Map SENSOR.
are your ECU caps good, if not the injector will misfire so will spark or as we know all code 41s is spark misfire and 41s cut fuel  at the injector, so that 41s would  cause the injector to cut fast.
if 41s, 42s are gone the injector must not misfire,  or CAps IN ecu ARE BAD. (NO CMP ERRORS CAM SENSOR IN DISTRIB.)

150 IS GOOD PRESSURE, COLD OR WARM ENGINE,

So what causes smoke black if no DTC errors and not  in limphome mode.
in order.
1:way too high fuel pressure, saw one old care that had a siillly huge fuel pump outiside  the tank off a FORD Crown Victoria, and it was so powerful it over loaded the  FPR all the time
like garden hose to a  fire Hydrant, wild..

2: gross misfiring,
3: map sensor reads wrong key on no start and key on idle voltage out, of MAP seen on my map table , see map page in fixkick.com type map there.
4: vacuum is wrong 19inches HG. at idle and steady not bouncing like mad. ever and for sure not while idling at 800rpm ISC working and controlling idle hot engine.

5:
The ECU may need new CAPS (called a ReCAP job) everyone Ive seen needed, a simple job if old school soldering is easy for or others.
engine not at 180f coolant,
6:
ECT not at 300 ohms hot but way higher ohm ,the ECU adds lots of fuel (too much for any hot engine)

T
hanks Kick. I put in another ECU, new injector o rings, new FPR. The injector is firing pretty well. NO DLC CODES. 
Im getting closer to finding the culprit - so my cold idle was very high and it was surging, then when warm it idled back down and then the rich symptoms started. While running, I unplugged the ISC harness, and then it seemed to idle better - and NO MORE SMOKE.  GREAT news !
The resistance of the ISC is 12.3 ohms and the voltage is withing range. good and voltage will be 1/2 of alternator/battery voltage, or 7vdc using only analog needle voltmeter (if not turn the bleed screw (hot engine) to 7vdc on the needle.
 The ISC looks new.
 I tried adjusting the air bleed screw on the throttle body as well as the adjustment screw on the ISC valve. 


I was able to get the idle down, no more surging, but its still running a tad rich.
ISC 5mm hex screw is factory set, but can be set to just lightly closed , just landing there to the seat inside.
For the ISC adjustment screw, I turned in CCW, then blew air into it while turning it CW until I could barely blow air into it, then just half a turn more CW.  I think it was turned out CCW too much which is why it was surging so much which is why it doesnt surge anymore. 
surging is the ECU doing that to the ISC< due to 800 RPM can not be attained, (ECU + ISC servo actions that)
in fact all air leaks in to the plenum can cause surging if 800 can not be attained, ECU controls that. only. at IAC. hot engine, cold is iAC controls all thermal.


For the TB air bleed screw - I turned it in clockwise all the way, and then half a turn out until hot idle is set at 800rpm. Now what happens is: 
  • When cold, it idles at 2500rpm, then it takes about 5 minutes of driving to slowly come down to 1000rpm
  • After 15 min of driving it fall even lower now, about 500rpm - so if I just the TB air bleed screw to adjust it now to 800rpm, I think when cold it will idle way too high now. So cold is too high of rpm, and stays high for too long if hot is 800rpm.   (the IAC is 100% thermal and the RPM is based on water temps the colder water is the higher cold RPM is all by the actions of the IAC WAX PELLET INSIDE, IT.
My plans: I ordered the TB throttle body gasket kit from Rockauto. I will be removing the throttle body and then cleaning the IAC and ISC ports and the TB air bleed port with carb cleaner. I will replace the base gasket using the correct "91+" in the set which you have photos for.  THIS IS A GREAT IDEA  AND THE BOTTOM GASKET MUST BLOCK THOSE 5 Tiny holes.
While the throttle body is off, I will also re-calibrate TPS. that is the best way and TV set to 0.0005" butterfly gap to 99.9% closed, FIRST (TV stop screw inspection first )
I will then do a rough ISC calibration    using the method you described where I turn the screw CW until the valve just seats (very minimal air flow) and then a half turn more. I will then re attach everything and then adjust the TB air bleed screw until fully hot idle is 800rpm. 
and ISC set to 7vdc, use a voltmeter, with real needle, even a $10 meter like that at walmart.  this needle tick averages the 200 Hz square wave signal on the ISC pins. 7vdc is it.

My stat and stat gasket and ECT sensor is new so that shouldnt be the problem. 
One side question: I did install a new radiator cap. The imprint says "0.9" (0.9 bar is 90% of 14.7 psi atmospheric pressure ) and is spec.
which I assume is 13 PSI.
My 96 16 valve kick has a "1.1" 16PSI cap. Do you think the pressure rating on the cap is too low?   no the difference is marginal. and the cap is crude, it is only a ball park number.


Thank You
Sina


yes get a needle analog meter like this. volts DC.


https://www.walmart.com/ip/DC-AC-1000V-V...hbdg=L1700


hot engine, 180f water
connect meter to ISC wire pair.
battery is at 14.7 or 13.3vdc (the lower number is float charge , higher number is fast charging, divide by 2.
7vdc is good goal at ISC (use the 10vdc scale or if your meter is 20vdc use that) DC. not AC.
turn the bleed down until it reaches 7vdc,  and that is now 50% duty cycle and even at high altitude the ISC works. right.  and 800 RPM held solid.

do this all after fiddling with 6mm hex screw on isc, set it for just lightly closed engine off. just kissing the rubber ringed seat inside.
if the  seat leaks a bet that is ok the bleed screw will correct that error easy.

btw your doing GREAT !
good luck to you and your little Sidekick.

Thanks! I will be doing all this today.
Can you clarify the 7v DC calibration for ISC? 
So you mean after engine is fully warmed up, I should backprobe the ISC terminals (red probe to light green wire, and black probe to blue/black wire), and then turn the air bleed screw until my analog meter gets 7 volts DC? The air bleed screw I should use is the throttle body air bleed screw, correct? Not the ISC adjustment screw which I already set when cold (valve closed).

Also when i have the TB off the car - should I be careful when cleaning the IAC? If I take the cap off, will the wax pellet be exposed? should I clean all of it with the IAC cap off (the 3 screw circular cap)

update: i took the TB off the car. THe bottom gasket was indeed incorrect. you could even tell because the gasket section covering the section where there shouldnt be gasket was heavily starting to deteriorate due to the vaccuum. 
I gave the TB a good clean and readjusted TPS and threw everything back on. 
Still trying to adjust the TB air bleed screw properly as well as the ISC screw (i think the ISC screw is fine since I screwed it until the valve started to seat. 
Once i get clarification on how to adjust the TB air bleed screw I'll set that to 7 volts hot.
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