Login Register

Thread Rating:
  • 1 Vote(s) - 5 Average
  • 1
  • 2
  • 3
  • 4
  • 5
1994 Sidekick 16v AT 4x4 4dr virgin ECM Ruby's still there
#1
I'm having an injector impulse signal issue that I found diagnosing a flooding issue. The ECM is virgin and has the Rubycon capacitors still in it. The ECM is in excellent condition and the Ruby's don't even look bad but the manufacture date on them is 9311 and 9302 so they are 27? Years old. I am going to do the repair myself  but I want to know if I should replace the injector transistors while I'm in there too? Everything else looks excellent on the board. 

Reply
#2
(09-23-2020, 01:31 AM)dieseldog69 Wrote: I'm having an injector impulse signal issue that I found diagnosing a flooding issue. The ECM is virgin and has the Rubycon capacitors still in it. The ECM is in excellent condition and the Ruby's don't even look bad but the manufacture date on them is 9311 and 9302 so they are 27? Years old. I am going to do the repair myself  but I want to know if I should replace the injector transistors while I'm in there too? Everything else looks excellent on the board. 

those are 1993 caps, made in work week 11 and 02. (of 52weeks)

what is the injector problem>  and is it on all 4  cylinders.

i presume all 4 spark plugs are wet with fuel, ?  

if the injector pulses are good,   0 12,0v volts the injector transistors are good.

lots of things cause flooding,  sensors reading wrong is one, FPR bad and fuel pressure way too high.

so does DLC, jumper (diagnstic) show CEL blink code 12< good or others?
key on CEL must blow, and go out running (nag switch turned off on federal cars)


O2 failed, stuck at 0v cause huge over injections.
mAF dead and in limphome mode, huge injections.
ECT reading way too cold and over injections. all of these are 4 cylinders all over injecting
only one injector over injecting is bad injector or as you said its matching transistor bad. 1 of 4) all 4 injector transistors do not blow up all at once.

how that helps some.
cheers
http://www.fixkick.com
Reply
#3
(09-23-2020, 05:56 AM)fixkick Wrote:
(09-23-2020, 01:31 AM)dieseldog69 Wrote: I'm having an injector impulse signal issue that I found diagnosing a flooding issue. The ECM is virgin and has the Rubycon capacitors still in it. The ECM is in excellent condition and the Ruby's don't even look bad but the manufacture date on them is 9311 and 9302 so they are 27? Years old. I am going to do the repair myself  but I want to know if I should replace the injector transistors while I'm in there too? Everything else looks excellent on the board. 

those are 1993 caps, made in work week 11 and 02. (of 52weeks)

what is the injector problem>  and is it on all 4  cylinders.

i presume all 4 spark plugs are wet with fuel, ?  

if the injector pulses are good,   0 12,0v volts the injector transistors are good.

lots of things cause flooding,  sensors reading wrong is one, FPR bad and fuel pressure way too high.

so does DLC, jumper (diagnstic) show CEL blink code 12< good or others?
key on CEL must blow, and go out running (nag switch turned off on federal cars)


O2 failed, stuck at 0v cause huge over injections.
mAF dead and in limphome mode, huge injections.
ECT reading way too cold and over injections. all of these are 4 cylinders all over injecting
only one injector over injecting is bad injector or as you said its matching transistor bad. 1 of 4) all 4 injector transistors do not blow up all at once.

how that helps some.
cheers
With the noid lights connected to the injectors, fully charged battery and fuel pump relay pulled had a buddy crank the engine and the lights would flash and then stay lit for a few seconds, flicker rapidly and stay on again. This doesn't have the nice little pattern usually seen on a healthy MPI. I had the caps replaced today on the ECM and the electrical engineer that did the work showed me the old Ruby's and tested them in front of me to show that they were in fact bad. One had low capacitance and the other had none whatsoever so maybe I am on the right track. If my issue isn't resolved with the ECM I'll start checking the components you mentioned.
Reply
#4
I just had a worrisome thought...
Should I test all the inputs and outputs to the ECM before I connect the repaired ECM? I am going to check for grounding wires and continuity. This will help me to sleep better tonight.
Reply
#5
(09-23-2020, 10:32 AM)dieseldog69 Wrote: I just had a worrisome thought...
Should I test all the inputs and outputs to the ECM before I connect the repaired ECM? I am going to check for grounding wires and continuity. This will help me to sleep better tonight.
so the check engine lamp is dead?  this is first step on all cars, 1989 to now.
the DLC has jumper pin , to make the CEL flash 12 code.  means Im ok.
caps are polarized so must not be put in backwards. (installed)

the inputs are fully protected, no need to worry inputs only outputs can blow up easy, (shorted to 12v yes boom smoked)

how does that happen, well things shorted on the  outputs,
the 4 injectors are 10 ohms  each. 12-17 some books show.

the relay coils (VSV) are about 35 ohms.

see my commented schematic yet?
I guess you have the 4 speed A/T tranny.?
one more output it it as pin a16
O2 heater , not shorted,(common) B23, the heater is 1 amp heater, or about 12 ohms but that is hot ohms, best is to have new o2.
iSC b12.  12 ohms (idle speed controller valve , 1 pin plug mounted to huge 16 plenum chamber top left side just in front of TB.

fuel pump relay a5  ,75ohms (see my links for better answers)
main relay A10 same as above same relay actually. as pump

.
so the NOID acts up?, but it sure can , if cranking mode. like that.  (key does the prime pulse is that the worry seening that odd pulse?)
but look for this on NOID tests only, oddness is all ECU processor controlled. if all 4 act odd that is processor on the ECU. doing that. (all that ) for sure all 4 acting odd.

Noid stuck on, is  shorted transistor, all 4 do not stick on,
noid dead, on one, open  NPN transistor or power wire does not reach this injector as you see power is ganged across all 4 injectors.
one noid weak (dim NOID), bad  injector coil shorts, or bad NPN transistor but surely not ever all 4 do this weak test failed.


that is correct RUBICONs dry out , not looks bad test bad. or weak. they all did that, parked in hot sun and caps hit 200F each ever touch a hot steering wheel on a hot day summer, all doors closed after opening, this damage is cumulative. but now fixed.
the ECU can last for many decades but it is the CAPS that short lived on all electronics just after batteries you do not have in there.
the transistors are not noted to fail at all ,unless and injector shorts are yours reading 10 ohms unplugged?  not 0, but 10. (about  10)

if any relay or vsv coil shorts it can and will blow up ITS transistor that drives it. this is what happens, with old relic none smart transistors seen today.


see pinout page ECU 16v



see bottom of page for ohms relays.




watch out for ganged injection most cars can do that in some conditions , I and not sure on this car, at all . 
Sequential or ganged  injection modes.  just know that it can happen on some cars or at some modes.
take limphome mode as just one example and I asked for code 12 DTC code (means) good if not code 12 that is limphome and I have no idea what limphome does, in TOTALITY.

limphome HITS and effects now,... (ecu sees dead sensors) 1 or more, and tells you via DTCs (flash codes, not 12s)
1: SPARK ADVANCE DEAD.  this alone make rich burn.
2: injectors go full rich, (crude injections) all 4 do that, not just one. (in 1996 this was reduced this side effect saving CAT from damage) (history here)
3: idle controls dead,(hot engine) the hot engine rpm controls are now dead, IAC thermal control is always working and is always off line above 150f. (closed)
4: RPM limits.

this is why DLC is used first to get code 12 or not .  if not code 12 that is bad sensors. (coded 51 excepted for bad EGR)
the ECU does not tell you if sensors are weak that is our job. only dead. (stuck low , stuck high sets DTC error)
http://www.fixkick.com
Reply
#6
i messed your post on injector noid oddities. (fully)
stuck on?
is that before caps or after caps, ???

if the caps are bad the regulators (VRM) go nuts, and if those go bad (5vdc reg) the CPU goes nuts and with that nuts so be injections and more.
GIGO in computer land means garbage in gets you garbage out and power is first.

The ECU processor inside (CPU) must have clean power 5vdc from its regulator inside ECU or the CPU will fail. and do anything bad really.
in the world of electronics for sure this, power is first, clean stable power, and is 5vdc inside there.
there are 2 regulators inside one for all digital electronics and one to run only sensors outside ECU. ECU pin B6, 5vdc., gray/red top of TPS. is here.
Bad caps cause the ECU to reboot , endlessly cranking, and the battery is dropping low, even to 10volts low, and this will cause noise that if reaches the CPU inside
it crashes and self reboots, and this can even fail in a loop cranked, even so bad you hear lots of relays in the car and VSV all clicking like mad.
that is dead CAPS HORROR prime, vast folks seen this now, in any DEGREE of better to worse.

the battery must be good and charged, this starter only uses 100amps so a 500amp/hr battery has no problem pushing 100 amps.
that means battery voltage stays above 11vdc, if yes the ECU works and the caps clean up the noise and all things happy feet, this ECU has no LDO VRM regulators inside, low drop out regs here, they are not near this quality.(legacy stuff)

recap it and test all outputs for shorts sure.
http://www.fixkick.com
Reply
#7
these cars came in to flavors, USA fed, and USA calif.
the fed car has nag light, that prevents DLC flash codes from happening
if the hood sticker shows FED car, then NAG is there. (i remove them for ever)
there is hidden switch in all FED cards up to 1995
my nag page is here, CEL in NAG lamp mode, blocking all DTC codes.

https://fixkick.com/CEL/NAG-Lamp.html

if the hood sticker shows word California, it is not a FED car and ignore this post.
http://www.fixkick.com
Reply
#8
Ok so I had the ECM done by an electrical engineer that does repair work on the side. He said that it needed to be heated up to 200°C in order to remove the old caps and install the new ones. I was able to watch him do the repair work I also had him test the transistors and he said that they were fine. One capacitor had no capacitance and the other had very low capacitance so they were causing my flooding issue I'm pretty sure. But now I'm thinking the ECM has probably been having issues for some time and the over fueling has been happening for awhile as well cause when I started it it was running horrible and the exhaust manifold got hot really fast and I thought maybe the ECM was toast but I thought about it for a minute and then pulled the catalytic converter and it ran great. So I think the over fueling killed my cat. What is strange is I can see through the cat. Do you think it could be my muffler?
Reply
#9
(09-24-2020, 12:51 PM)dieseldog69 Wrote: Ok so I had the ECM done by an electrical engineer that does repair work on the side. He said that it needed to be heated up to 200°C in order to remove the old caps and install the new ones. I was able to watch him do the repair work I also had him test the transistors and he said that they were fine. One capacitor had no capacitance and the other had very low capacitance so they were causing my flooding issue I'm pretty sure. But now I'm thinking the ECM has probably been having issues for some time and the over fueling has been happening for awhile as well cause when I started it it was running horrible and the exhaust manifold got hot really fast and I thought maybe the ECM was toast but I thought about it for a minute and then pulled the catalytic converter and it ran great. So I think the over fueling killed my cat. What is strange is I can see through the cat. Do you think it could be my muffler?
I keep asking if the CEL lamp does DLC code 12. on demand.
any time any car runs poorly we do that, on 1996 and newer cars OBD2 scans, USA cars.
older all have  jumper you insert in to the DLC, and i blinks out code 12 for good,any code higher than 12 is bad.
The cat will melt if engine goes way to rick rich,
yes these cars the cat can also breakup in to chunks and lodge in the muffler and clog it up too. 
200 °Celsius = 392 °Fahrenheit,   this will wreck any ECU, made, in an oven,  pins in the ECU are 60/40 lead solder .  I think he meant soldering gun temps only here,  I will chock this off as bad comms. from the soldering man.

The engine and EFI (ECU) has many causes of flooding (way to rich)
1: HIGH FUEL PRESSURE, we check this first, and we test the FPR fully , most of these orig. FPR are now bad,  the FPR is dynamic, with engine load.
2: ECU stuck in limp home mode.  (you will never know this unless you use the DLC jumper, this is first things first test, and NOT DONE yet why? IIRC
3: one injector only rich ,can be bad injector or ECU bad. (inj, transistors)  see one spark plug reading rich black or soaking wet tip in fuel>?
4: Gross misfiring.  spark bad in any way, will cause gross rich condition,  on all cylinders or just 1.
5: Bad engine, cam belt slipped, compression at 80psi not 180.  (12.4bar is good not 6)
A: As a result of any or all of the above, the CAT will glow red, and then melt or breakup or any of that.
B: if the cat melts engine vacuum is horrible effects. just  horrid. and no engine power. 


First we test the engine, we never blame the ECU first (ever ) well bad caps sure, but if you buy a $400 refurb from CARDONE 1,  and you are back to sqaure one how will that feel? blame ECU last after caps are fresh. last.
the rules are simple really,
Scan the PC first. code 12 ,  1995 method. paper clip jumper, why wait it is a 5 minute job, what if the ECU told you the MAF is dead , why skip this:?
engine is first. (compression tests and  vacuum readings all good or all bad.) if bad compression the cam belt slipped, as the all do.
then if all that is OK
there is also a cat back pressure test . see test 2 or 5  seen here. kickfix.com
check spark timing with a timing light, a $20 tool. if timing is way off the cam belt slipped. (again ?)
check spark plug tips, for SIGNS,  (color, carbon black ,white ,green with antifreeze , soaked in brown oil, dripping in fuel )) oldest test there is for 100 years engines USA. (world wide) otto cycle engines, petro/gasoline.
next?
if engine tests check out ok , the engine must pump air or the ECU can not inject correctly  , the ECU will not like a  very bad engine) ever
the ECU only compensates for normal wear, and altitude and driver demand.
next up is fueling tests, and fuel pressure at keyon (nostart) and idling tells you if FPR is good or bad.  36 KO,  30psi idle (bar:
a 6PSI difference or the FPR is BAD ! fuel pressure regulator = FPR, bad. and is now COMMON on all cars this old. super common in fact.


KEY On Bar: KO= 2.5 bar
idling Bar: is ,  2.1bar,     note the change in fuel pressure. here. it drops  and must drop.  THE ECU will never  ever run right with any BAD FPR that is for sure.
http://www.fixkick.com
Reply
#10
this tool, a good tool does all pressure standards, like Bar./KPA/ PSI, ' and inches-Hg, and this guy can do fuel pressure and vacuum both on 1 tool.
nice no.
I post this lacking what county you live in,  some in Canada still use imperial measurements,(a USA sickness that) but EU uses ISO, metric,

[Image: s-l1600.jpg]
http://www.fixkick.com
Reply


Forum Jump:


Users browsing this thread: 2 Guest(s)