91 Tracker CEL light glows

[ORF-tracker]

'91 geo tracker 4WD Auto. So my tracker acted up the other day driving and the RMP guage went up and down and car stalled and then the clicking sound from the Fuel Pump relay. I got a CEL code 12 at that time, but it would start, clicking sound and eventually stall. I got towed home.... So I bought a new fuel pump relay. Now I cant get the CEL to go off. Ive pulled the dome fuse and negative cable. Ive disconnected the NAG switch.

Is my ECU dead? I havent pulled it yet.

thanks!

[fixkick]

my mail , notifications are busted, so did see this, sorry.
so dont pull the dome fuse, first read out the fail code, write it down and then clear the ECU by pulling the dome fuse. and post them, those DTCs.
that clicking is bad, and i have a clicking page, search clicking.
but is bad caps in ECU or the fuel pump is overloading the power supply 12v to the eCU.
the pump draws 4amps,

what to do is easy buy a rubber hose, and find all parts that click, by putting that hose to ear and getting other end near all relays under ECU, and at VSV solenoids right front of engine.

here is the link to my clicking page.

it sounds complex but is not
if the ecu power 12v is bad, (car body, wiring) then the ecu will in fact keep booting over and over, and each time all ecu acutuators click, the key word here is ALL or most, not just one.
see?
but if power is good and they click over and over that is a bad ecu.
on some years the 02 sensor wire shorts to the exhaust and bingo, slams power to the ECU. the 02 sensor pink wire goes to main ecu power blue-black , these 2 wires must never be allowed
to short. or the ECU will CRASH (reset and reboot)


http://www.fixkick.com/ECU/clicking/clicking.html


the full schematic is here.
http://www.fixkick.com/look/91-complete.pdf

the bad ecu page, easy fix. new caps is here
http://www.fixkick.com/ECU/ECU.html

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btw. if you car has never had the ECU looked at ever, that is , its still in its factory fresh state? no rebuild stickers,
then the caps must be looked at. all the rubicons failed, that year, so they are either original or replaced. only looking solves that riddle.
if some one put in new nichicons, in there , then they are good.

"Nichicon UPJ series, we'd not be reading this...." cut pasted here, caps come in grades, not just values.

[ORF-tracker]

my mail , notifications are busted, so did see this, sorry.
so dont pull the dome fuse, first read out the fail code, write it down and then clear the ECU by pulling the dome fuse. and post them, those DTCs.
that clicking is bad, and i have a clicking page, search clicking.
but is bad caps in ECU or the fuel pump is overloading the power supply 12v to the eCU.
the pump draws 4amps,

what to do is easy buy a rubber hose, and find all parts that click, by putting that hose to ear and getting other end near all relays under ECU, and at VSV solenoids right front of engine.

here is the link to my clicking page.

it sounds complex but is not
if the ecu power 12v is bad, (car body, wiring) then the ecu will in fact keep booting over and over, and each time all ecu acutuators click, the key word here is ALL or most, not just one.
see?
but if power is good and they click over and over that is a bad ecu.
on some years the 02 sensor wire shorts to the exhaust and bingo, slams power to the ECU. the 02 sensor pink wire goes to main ecu power blue-black , these 2 wires must never be allowed
to short. or the ECU will CRASH (reset and reboot)


http://www.fixkick.com/ECU/clicking/clicking.html


the full schematic is here.
http://www.fixkick.com/look/91-complete.pdf

the bad ecu page, easy fix. new caps is here
http://www.fixkick.com/ECU/ECU.html

---

btw. if you car has never had the ECU looked at ever, that is , its still in its factory fresh state? no rebuild stickers,
then the caps must be looked at. all the rubicons failed, that year, so they are either original or replaced. only looking solves that riddle.
if some one put in new nichicons, in there , then they are good.

"Nichicon UPJ series, we'd not be reading this...." cut pasted here, caps come in grades, not just values.

(The ECU was OEM, never rebuilt, and had the infamous rubycon caps...)

Ive taken care of the clicking sound which was in the FP relay, it clicks now but only once or twice at key turn, I assume this is normal.
But after the FP relay replacement, car starts, the CEL remains ON, cant get code 12 or any codes, even after multiple battery disconnects and dome fuse removals.
No clicking at the relays in front of engine.
So I bought the 3 main caps you recommended from mouser and had a TV repair place install them. 2 of the caps were leaking.
Installed rebuilt ECU, car starts, but continues to smels rich out the tailpipe, and after warmup, continues to only idle at 400-500rpm. Still, CEL remains on, cant get any codes, even after multiple battery disconnects and dome fuse removals. I'm going to get a known good ECU to swap in and see if my old ECU is dying...

US Federal '91 Geo Tracker Softtop 1.6L 8V 2DR 4X4 3 spd auto CAMI RWAL A/C 152,000 miles

[fixkick]

bad caps, they all do that, 89 to 95.
ok low idle, rich.
if the corner cap leaked acid, it loves to eat up a trace there,, under it, causing odd behavior, , can go to DEEP BACKUP mode, this is worse than failsave (limp) mode. Backup mode is when everything fails. (inside ECU horrid rich conditions and no advance of timing,etc)
you said the nag switch is unplugged, its 3 wires. so that,can not cause false CEL nor stop the eCU from flashing its codes, as it does always does when active.
No 12s is a bad bad sign.
the old ecu can be fixed, but it takes very careful, bypass jumper.
Does this ecu fail the 5vdc test ? that is, the 5vref makes it to the TPS? 4.75 to 5.25 is the spec, range to read.

pin A34 (white conn, is A)


one common failure is below , see the CAP C111 removed. see the + sign, ?
that pad has a feed-thu- called VIA's and can be gone, killing the VIA power pass through at this point, it can be fixed, but do not drill this PC to do that.


http://www.fixkick.com/ECU/hell/html/image_7.html

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sorry at Pin A23? 5v

[ORF-tracker]

Well I got a Cardone ECU in today. Spent the money, wanted the warranty and confidence. Cardone part number 77-4367.

Fired right up-> CEL is off, getting code 12, idles at 900 when warm, and doesn't smell rich out the tailpipe. Also passed the +5Vdc test at pin 23A (TPS) on the new ECU. On the old ECU, cap c111 was installed properly btw. You were probably right on the feed thru being damaged.

Thanks again for all the help your site provides. I probably wouldnt have bought/kept this tracker if I didnt have access to such good info. I'm sure you'll hear from me again one day.

[fixkick]

in texas , we have a saying , you quit school , cuz they had recess.
nice, work and very glade, you can get it smoke free.
Yes, Cardone does make a good product.

you are welcome and do come back, all the best to you.