94 Tracker woes

[MattV]

I just stumbled upon this page a couple days ago. I've read a lot so far but I still haven't been able to pinpoint my problem. I have a 94 2dr 8v 5spd 4wd Tracker. I got it 2 years ago for free, saved it from the scrap yard. I have no driveability issues from cold start to work(~13 miles). My issues arise on hot restarts and they're intermittent. I sometimes have to use the flooded mode start with the pedal to the floor. Then I'll have a high idle at about 1100 RPMs. When it idles at 1100 just the slightest blip of the throttle and she floods and dies. Once I get going I have to keep it above 2200rpm(which really isn't that hard) because there is no throttle below that, just a high idle. If it wants to it will idle at 800 and everything will be temporarily ok. I obliviously threw the easy parts at it first complete tune up, then I ultrasonic cleaned the egr and the IAC(at the good 800rpm it runs so smooth now). The IAC has 12.3 ohms and opens with 12v applied, by the way it tastes terrible. Then I assumed it was the FPR and I threw a new one of those at it to no avail. Well this all happened over the course of the past 2 years. I'm at the point where I started googling and I ended up here. My next step is getting the fuel pressure readings. That's tomorrows project.

[fixkick]

ok as you saw all 8v engines race fast , with any vacuum leaks from any source, and with full engine power those leaks
in fact the drivers right foot is just one more big leak of air /vacuum.
what are the symptoms now, after all those changes, im not sure.
flooding?
the new FPR prevents any possible over pressure of the fuel pump so is not fuel pressures, your FPR is only for altitude changes.
what does it do good or wrong now.
still hot start flooding?
is the injector orings leaking ,can be eye ball tested
are those 2 injector wire molested in any way? (many are like this do to ignorance of how it really works, see jump wires here ,bad news)
does ECT read 300 ohms unplugged HOT? if not, flood city happens.
is the diagnostic, jumper showing code 12s only for GOOD.

[fixkick]

what is compression, warm or hot, 155? or 75 PSI, done WOT
is spark timing right, ? if way way retarded the cam belt slipped, was it changed at 60k miles, oops, if not.
if the belt slips ,power loss,and flooding, or worse the crankbolt now set to 94/ft/lbs per suz, service bulletin . seen on the belt timing page.
if ecu is in limphome mode, same deal, floods.

id do flash code 12 first. really its only a 1 cent paper clip... why skip this first first test
?

[fixkick]

all old EFI cars, really TBI , focused
1: fuses
2: flashcodes 12.
3: wiring hacks to the injector
4: ECT ok.
5: not in limphome
6: crank bolt 17mm not loose but to new spec.
7: SPARK TIMe not way off, is use see #6 or belt did slip, cam belts never last for life of any engine.

[MattV]

Yes code 12 is what I have. The timing belt was just replaced about 1500 miles ago. Ignition and cam timing are correct. I removed the crank gear when I replaced the front main seal. It wasn't loose. I honestly don't think it's in limp mode because it runs fine when it runs fine(if that makes sense). I'm still averaging 25mpg(when it runs fine). I did not do a compression test yet. The wiring to the injector is fine and not mangled. I do have to check the ECT but I think I changed it with one from my parts stash when I first got it.

[fixkick]

i agree
code 12, just means no shorted, nor open wires to sensors, it only find totally bad sensors
but is good to know that.
the ECT was 30 degree low the engine would run rich but no codes. huge error, there, but ECU can not know this, no points of refrence to tell you that, so 300 ohms hot, sensor unplugged, key off, is 5min test. and bam, ECT is reading correctly
my ECT page shows, this and even shows volts, and the math to arrive there.

The hot start failures (and floods)
can also be a leaking injector, so ,with the air horn off, key off a running engine, see that injector halt injections in an INSTANT
as it must, with zero power to it now, (keyed off) zero leaks allowed now.

code 12 means not in limphome, but ecu can get lost.
lost means it can't control fuel.
i don't think its lost... (high fuel pressure, or 02 stuck at 0v) total loss is fuel pressure dead wrong, partly lost is 02 dead.
i think the injector leaks or its 2 o-rings cracked, assumes ECT reads 300 ohms and IAT read ok.
The map sensor hose can clog or cracked and engine would like to flood... but 25mph hints that that is not happening.
but I always check the full vacuum path to the map,its the main sensor for fueling.. .

hot starts, use the ISC for air(electric)
the IAC thermal unit in base of the throttle body is closed at 150, and up. so does not provide start up air, ever hot.
but the ISC +bleed ,provides all startup AIR hot, TV is closed,
so if the ISC fails to open , the engine will flood, unless you add 5% more air with your right toe. a good clue this.
Isc can do very add things...
most leak,
but some jam or only under odd conditions. (even dirt in the back side guide sleeve)
keep its mind all cars go super rich cranked if the ECT lies, its buns off. it tell the ecu that you are in alaska, it will flood.
the ect fuel tables are very very accurate, here, In fact this is why EFI runs in all places on earth, Alaska to Death Valley CA.
those magic tables.. for fuel vapor pressure.

[fixkick]

btw there is not just one ECT,
if the wrong one is used,all hope is lost....
if in usa,most the ones sold are correct. SMP sells it. and is correct ,ive tested it 100%
but not world wide,,, they are NOT the same and neither is the ECU.
nor mix in other model suzuki car parts here.

[MattV]

I got home from work, pulled right into the garage, and checked resistance on the ECT. I got a reading of 987 ohms hot. I was able to find a new one at autozone. Sure enough I'm pretty sure all is good now. I couldn't get it to flood on me. I tested the old ECT after it was sitting on my bench for awhile. My reading was 280ohms. So I then set it close to my kerosene torpedo heater with it connected to my multimeter. Resistance just shot up over 1k. I don't understand why I had intermittent flooding which seemed mostly to happen after hot restarts. Heat soak on the ECT? Before I feel like I could have driven an entire tank of fuel off of a cold start without any issues. If I would have shut it down and restarted after normal operating temperature I'd have a 50/50 chance of it flooding.

I'd like to thank you for your help. How is it you've come to know everything about these little Suzuki's? This problem I've had with this tracker is one of the big reasons I got it for free. Supposedly a couple shops couldn't figure it out before I got it.

[fixkick]

bingo wrong 1000 ohm is 100f
hopeless that.

room temp is 2500ohm
so that sensor is not even NTC< so is double wrong. (wrong and backwards)
flooding, can do all kinds of thing,,, the spark plugs hat it, but recover, be cyclic....
dont forget yours, was PTC, and ours is NTC, total opposite.
I restored 3 of them and sold 4
yes, putting in wrong sensors will cause ECU huge problems
and is not a smart ECU
smarter ECU can see the cold start is dead wrong, key on, and iAC = ECT if not BAM wrong, set DTC errors.
yours is old , slow and dumb. but that does ,make it hard to diagnose, lacking a scan tool
with the too, plugged, 100f hot. oops. 1 second later , bingo... ECT OR MISSING THERMOSTAT. HAND ON TOP HOSE.OOPS ECT
If you themostat is 180 or more , car gets fantastic MPG.

good luck and happy trials.

[fixkick]

sorry forgot to show you,,, here is our USA scale

http://www.fixkick.com/ECU/temp-sensors.html

basically the IAT is just a faster , ECT