jump started tracker

[seed]

1991 tracker

My dad used his tracker to jump start a lawn tractor and now it won't start. It turns over fine.
It has throttle body fuel injection. If gas is poured in (throttle body) it will start and run until it uses up the fuel. He says it is getting spark and the fuel pump is working fine. He changed out the fuel filter and checked all the fuses...all are ok. It gives trouble code 12 with key on and when turning over so I assume the ECU isn't the problem.
Could it be the fuel pump relay? Ideas?

thanks

[jtgh]

sure it can be
bad ecu ,
bad fuel pump.
bad fuel pump relay.
bad main relay,(no it cant code 12 is good) Ecu has power.
or bad injector driver in ECU ( i have pn) (see bad ecu)

what you do next depends. depends on what tools you have and how hard the path becomes.

if you have access to a noid light you can check the injector signals. ( you can make one) but no , lets just listen to the pump. Free test ,no tools.

but id check for the fuel pump buzzz at the tank cap hole.
1 turn key.....
ah heck here it is
Pump is dead ,now what

(no pressure)
(no injection sig)
on or the other.
2:

[seed]

He says he can hear the fuel pump run. I mistyped in my original post. What I meant to say was could the problem be the fuel injector relay? Jerry I read through your site but couldn't quite grasp how to check the injector signal.
Could you give me an "injector signal check for dummies" type of explanation.
Also, are there any fusible links that could've blown?
thanks again........

[CodyJ]

Remove the box next to the battery and take a look at them (the fusable link fuses); also check your FI fuse if you believe any fuse was blown. I bet you're 25amp FI blew. Give that a try -- goodluck! They are under the driver side under dash.

[jtgh]

you have power to ecu and to fuel pump relay , if the FP buzzes it has power.
I hope full power.

yes, just attach a light like this across the injector.
http://carfix.stufftoread.com/NOID/91-noid-sf1.jpg
this photo is same exact car as yours.


do it with injector connector , unplugged and if flashes cranking.
then with injector pluged in with both lamp and injector attached (loaded test)

usually the first test fails if the ecu is bad.

2 things here.
do you have 30 psi pressure on the test port of the Fuel filter
and did you replace it. the filter, ( they do clogged and are a service item)

after you have pressure. ( forget ecu , if spark is good, it is) and now consentrat on
the NOID LAMP.

no injector pulse and the engine will never run.

that is all there is to this.

[jtgh]

use my lamp
or an led ,but the led is polarized and may flash too fast to see.
the incondecent lamp , makes the pulses longer so you can see them.

very special lamp, see low current ? very important that.
a brake lamp will not work.

cheers.

[jtgh]

testing injection

see red box of NOIDS.

they rent these cheap.
i got a whole kit of them for $15 new.

cheers.

soon as you pull the injector plug ( attached to TPS plug) TBI 8v.
check the injector ohms, (1ohm is the resistance reading ) open is bad, as is infinity which is open.

[seed]

I have a noid lamp on order. If, after I use it, it doesn't flash does that mean a bad relay or ecu?
Is there a fuel injector relay or only a fuel pump relay? How exactly do you test a relay?

[jtgh]

ECU makes no injections when:
NO SPARK. (yours is good ,right?)
TPS signals W.O.T. (wide open throttle)
dead ECU. (sorry, RIP)
one last possibility ( rare) shorted injector, or open injector)
measure the coil resistance, 0.8 to 1.2 ohms (short meter leads to find zero point and do the math to correct for low ohms errors.)
short leads ,read .5 ohms, check injector, it read 1.7 ohms , minus .5 - 1.2ohms pass.
see? use the lowest range on ohms, if meter has instruction read them.
it may say "to null out low ohms, do the following xxx"
see? then you can test for a shorted injector after nulling out the lead resistance.
sorry for complexity here, but this is life in the fast lane.....lol

so if injector driver is dead (NOID) (last week some passed the Noid test but drive was bad, in this case have the light and NOID connected as same time .

then check TPS
and if that is good, the ECU ( if cel glows and fuel pump runs, ecu has power)

I have the pn for the transistors , that drive the ECU and a source. if you want to shot gun them.
Make sure the 2 wires for the injector are not grounded out to the body.
or the new ECU will blow out again.

[jtgh]

tps test and injector tests are on my fast sensor test page.
see it.?