1991 geo tracker doesn't usually start in colder weather.

[fixkick]

to my surprise later , it seems you failed to look here, see that red arrow there, this is out of the offical book SUZUKI, on THIS CAR. its not a generic drawing at all, its is the REAL DEAL here.




pump connector on a Toyota PU. what do you think this does hot/cold/wet/dry ? answer anything it wants, IT'S BAD.

[fixkick]

the factory service manual covers the pump.

The only difference is the tank is bigger (and deeper on 96+ ) and a newer ECU that still does the 3 second rule, unchanged.

https://web.archive.org/web/201011190942...6C-pdf.htm

page 6c-6 page 6 on.
pressure relief steps
then drain
then drop.

in that order.


omg figure 6C-10 on page 8, shows the bumper connector there, gee this is step one not last.

[wildfire]

Thanks for your feedback fixkick. Well, the geo tracker didn't start up today. I didn't hear any 3-second buzz at the fuel pump either. (the weather has even cooled down a little, but not that much) I tested for power again going to the left taillight, when the key was turned on for first 3 seconds ( test lamp came on okay). Expecting rain next few days, so will have to wait before I decide to drop the fuel tank and check the wiring, since I hate working in the rain.
Just wondering, ...the fuel relay 3-second prime should still work right, even though I'm getting low on fuel.?

[fixkick]

..the fuel relay 3-second prime should still work right, even though I'm getting low on fuel.?

ive no idea what low means, 1 cup , 1 gallon 3 gallons?
the pump will pump fuel only if
the tank is level, and say 1 gallon or more fuel.
Ive no idea at all how any pump SOCK fits into any tank bottom after all there are like 5 aftermarket tanks sold. and many were replaced long ago.
Id guess 1gallon minimum (I really hate to guess but there you are) if the tank is not level it sure can suck air. with 1gallon.
if the pump sucks air it makes more noise, not less. (after all its now sitting in free air space and not submerged in fuel.)
THE ecu NEVER KNOWS PRESSURE IS WRONG, EVER. it just does the 3 seconds blind as a bat, and dumb as a brick, it is JUST a 3 second counter inside the ECU. (deep) (this statement does not hold true on NEW cars with rail pressure sensors, and more smarts)

here is what happens and why.
the key is turned, from off to on
if the ECU has DC power, the ECU then turns on the pump for 3 seconds
the ECU is the timer, (soft/firmware instructions inside do that only)
this is called the priming pulse. it attempts to charge the fuel lines up to 34 to 41PSI, (41 is very common at sea level, FPR does the regulation now)
The priming pulse ends, and the pump goes silent.
if you crank the starter, the pump runs at 12vdc full time cranking, there is no 3 second rule cranking ever. so that too is a valid test.
but you cant hear any pump cranking, so...

we know the pump is failing
we dont know why yet
after all the wires to it can in fact be bad, and is super common on any old car.
and 10x that in the SALT BELT states.

https://en.wikipedia.org/wiki/Salt_Belt

[wildfire]

The reason I let the fuel run low, is because I want to empty it anyway, before removing the tank. No, I wasn't able to get to the rear bumper connections yet. I will try that next, thanks. Did you have to remove the bumper first.?
So my understanding is the 12vdc 3 second prime should function whether there is gas in the tank or not, when I turn the key to on without cranking the engine.?

[fixkick]

LAST RULE
THE ecu DOES ALL THAT FOR A GOOD REASON
IF YOU wreck the car and the driver tries to start the car (bad idea), it will not dump vast amounts of fuel on the road, starting a huge fire.
the 3 seconds limits the size of the fire and the carnage if the pump were ran full time.(key on, engine off)
i call that the anti - crash and burn feature, as seen on TV.

[wildfire]

Update: I was able to reach and back probe test the wire connector above the gas tank, after removing that black metal bar at the back under the rear bumper. It appeared in good condition and lit up my test lamp for the 3-seconds, but no buzz sound from the fuel pump. I then proceeded to lower my gas tank after pulling off the rubber hoses. (It has a skid plate attached to it). Since I did this about 8 years ago, most the screws and bolts weren't too difficult to loosen. I couldn't loosen the fuel line nut attached to the top of the tank, so I removed the rubber gas hose line at the fuel filter instead. After loosening the screws and pulling the fuel pump out, I noticed it had a lot of minor chalky corrosion stuck to the pump and assembly, (not rust) probably because the gas tank hasn't been full for a long time. The wires that were attached to the sending unit assembly were a little green maybe a poor connection. However, the pump itself was an ultra brand, which Napa said was their cheapest fuel pump they carried.

[wildfire]

So fixkick, Now that I have the fuel pump and assembly removed from the tank is it okay to check for the 3 second buzz *(not crank),
(still some gas at the bottom of tank) or should I put it back in the tank after cleaning it up, and test it there? In any event, if I should upgrade the pump, what brand might you recommend, and do you think it would it be worthwhile changing the whole pump sending assembly. I see some on eBay, but there might be better options. thankz

[fixkick]

ok
sparks and fumes, are a bad mix.
but here is how to do it, safer....
make up jumper wires, (black and red are nice or black and some other color, run black to black and pink to color and color to battery PLUS LUG.
pump
black >>>>>jumper wire black to battery NEG lug.
pink >>>>>jumper wire to color wire, to battery PLUS lug. do this last this end. hear pump run, no smokers about (odd neighbors smoking too , snoopers)

the book on the car and (schools) tell you to put a 15amp fuse inline with above hot wire (color) so if the pump is shorted the wires do not burn up in your hands or worse , in or near fuel, boom.


3 to 6feet long, 6 is better jumpers.
connect it to the pump top wire pair , (unplugged)
then other end hot wire, across the battery.
get the polarity corrected, use gloves. so if the wires get hot, no burns.
it will spark at the battery end, that is where we allow the spark only there, the pump draws 4 amps when new. and the spark will be 4 amps, effects.

let it spark only at the battery.
but the pump if good ?, is going send fuel flying if any pump output hoses are open ! be ready to catch it in a bucket? or huge rag?

the pump will now run as long as the battery is connected, its just an electric motor in the pump DC brush motor. just like a wiper motor or cab blower.

run for 10seconds max or the pump if goes dry , will wreck the pump.

the 3second is in the ECU not the pump. the ECU brain counts to 3.
the pump is only motor.

OR?????
to test the pump on the floor but wired to car? only?> that It.?
then sure you can, just keep the pump wet.



So fixkick, Now that I have the fuel pump and assembly removed from the tank is it okay to check for the 3 second buzz *(not crank),
(still some gas at the bottom of tank) or should I put it back in the tank after cleaning it up, and test it there? In any event, if I should upgrade the pump, what brand might you recommend, and do you think it would it be worthwhile changing the whole pump sending assembly. I see some on eBay, but there might be better options. thankz
[/quote]

to

[wildfire]

Yes, that's what I meant, the second option... to clean all the connections on the pump assembly and then rehook the wiring to the car to see if I get the
3-second buzz, while the fuel tank is still laying on the ground (concrete) under the car.