92 Tracker Won't start

[Kirkd]

JTGH,

Ok got the ECM out. You should warn people to have small hands and a good Snap-on # 2 Phillips to get those tight screws out (the later I had) I see dreams of what might happen if you rounded the heads off of the screws. I picked up three caps today at a local Elec supplier all NTE and don't know if they are any better than RS stuff or not? the C-111 63-100 and the C103 63-47 are both smaller and the C101 63-22 is bigger. I notice all the ones I am replacing are 50V not 63. Guess thats ok?
At this point I am just a "parts replacer" And I can do that.

Please advise before I do it. I could wait and order. What do you think?

Thank you

Kirk

[jtgh]

you are correct those are beefy screws.
when i die someone gets maybe 50 odd phillips drivers. cant have too many.

run them. they will work. my link is for people in the boondocks.

your doing perfect.
just uses 60/40 rosen core solder. no acid.
look at old caps, and see markings.
that strip signifies the minus side of cap, just make sure you put them back
- to - + to +
or they will rupture when powered up.

remove the old solder with cheap solder sucker or solder wick wire.

50 and 63v are both good, its like 50% on every other board.
after replacement you can be assured the ECU will have quiet 12vdc buss.
automotive dc power is very noisey.

after doing all this , wash before eating as it is lead.
lead is safe so long as you dont smoke or eat , while working it.
have a fan near by is good too,

my ecu page shows ESD procautions. (mostly a problem in dry climates).
i have a cheap ground strap but you can just wrap any old copper wire around wrist and ground other end to ecu corner ground screw hole.
this keeps body charge equal to the ECU.
some buildings with super powerful air conditioning have horrible ESD , environs.
another tech, is to just keep resting hand touching the ground screw first before right hand does its work.
This is an old trick of computer workers. touch case left , pull part right.
hope that helps.

if no injection now, then we must replace those 2 transistors.
they can be tested, if you feel confortable removing them and then using a Multimeter with a diode testing switch position ,
these are easy to test.
dont forget to look at the closely with a power ful lamp for spilts , melting or burn marks.
and the resisitor that goes to the pull down transistor.
r225 must read less than 1 ohm.
look for over heating signs.

the only way to prove the ECU bad is put the noid lamp at the output conn.of the actual ecu ,but that is a big pain.
it is the wires or the ecu, if TPS is not bad.
that should prime your pump..

cheers.

[Kirkd]

JTGH,

To bring you up to speed on this I replaced caps and still noid. So I sent it off to the guy on Fleebay for rebuild. Got it back yesterday and still no start. I do have NOID pulse now (at the back of the ECM and the Plug). This is what I get for volentering my time to my 85 year old Dad! Oh well I would do it again in a heart beat for him.
I rechecked fuel pressure and spark.

Thank you

Kirk

[jtgh]

many folks find 2 problems , on these old cars.
yours is , :
recapping:
8v 92', weak #4 cycl ata 90 psi
perfect fuel pressure.
new cleaned and tested injector.
and noid is flashing now (was not before)
good spark and timing close to 5-8deg before TDC , good to go timing.
starts up with instant start spray !
8 valves engines one can watch injection !

and next look down air horn , it must spary fuel.

there will be no injections if no spark, but since you have NOID flashing.
the injector is firing. so ECU is happy about spark.
is the noid flashing while Injector is connected?
back probe the injector connecter with needles to connnect up , noid lamp.

id look for the spray at the injector and works backwards.

your down to 2 , probables.
1: injector wiring is open.
2: tps output tap is at 5v ( can be caused by bad ground at tps)
you see if tps loses its ground, the output pin pulls up to 5v and this is wide open throttle. WOT = UNFLOOD MODE. all injection stops.

if the NOID flashes with Injector wired into circuit and not fuel flows.
then the pressure has dropped to zero.( some fuel pumps work 1 min. then die next)

did you check the notorious ground for FP at the left rear tail lamp?
remove lamp , look in, see ground lug , it loves to rust there, causing flaky pump.
2pm position.

you might have to look at 3 things at once.
air horn injection view.
fuel pressure.
and noid.
if all 3 are good. then injector , noid lamp is lying to you.
some will flash when signal is weak.

that being the case , some folks here have wired in new injector wires from ECU to injector, just to cure random opens in harness.
one guy lost all hair trying to find that open.

we are very close.

cheers.

[jtgh]

http://carfix.stufftoread.com/TPS/TPS-p91.JPG


pin D is ground.
Pin B is out put and must not be close to 4v, or car will never start. (unflood command)
pin A is 5vdc all the time. (power refr. from ecu this is)

the tps and its wiring can cause injection to fail.
i do not think that is your problem, I only mention it becuase it can cause 100% injection fail.

it seems to me (guess?) bad wiring at injector or intemittant fuel pump.