1G Injectors not pulsing.

[Jankenshank]

back one again with the renegade masters.

car ran 500 miles before i swap'd chassis,

its a 90 engine and engine harness mounted in a 91 chassis and 91 body harness.

car turns over fine.
coils are sparking on all four coils in sequence.
fuel pump is constantly running and pushing 40psi of fuel to rail.
engine is mechanically sound

Injectors are not purging fuel into cylinders.

CAR WILL START AND RUN WITH STARTER SPRAY.

checked the ECU - visually looked for burns on the circuit board, as ignition is turned on CEL turns on and goes off after 5 seconds, boost gauge goes to 0. also ECU reacts/logs normally on ECMlink,

checked resistor box - it is connected to the connector with the yellow and black wire, also swapped out with another box, no change.

swapped MPI relay, no change.
swapped #19 fuse in driver fuse box, no change.

hooked up a volt meter to injector clips - receiving 12.6 volts on both pins on all four injectors.

swapped out injectors - no change.

the only other thing that i haven't swapped is the CAS. getting one from work tomorrow.

the only thing that has changed is the 91 body harness. is that my issue?
there were four unused wires off of the 91 engine harness that were not used in the 90, heres my thread on that.

http://www.dsmtuners.com/forums/electrical-tech/331216-90-wiring-harness-94-one-plug-deference.html

is there anything else that controls the injectors?

any other ideas are greatly welcomed.

cheers janken.

 

[Tooltrt87]

I had the same issue with my 92 i was driving and my inectors stoped pulsing. I know you siad you check the fuse in the car. The promblem with mine was the fuse blew but my fuse is on my positive terminal. I dont know if you have it on a 91 but id look there.

 

[rlacasse1]

Have you checked if you are getting power to the resistor box?

Also, have you checked the plugs at the injectors to see what you get when you are cranking the car over? Oh, just reread it and saw that you have.

At the injector plugs you should have one wire that is a constant + power wire, and you should have one that is a pulsing ground. In your post it sounds like you are saying you have constant power to both pins, which is wrong.

 

[1gdsmftw]

how are your harnesses wired behind the ecu and next to the air box on the passenger side? if those are mixed up you could have an issue their! and i have a 91 green top cas if you need one jack! just come and get it

 

[Jankenshank]

switched the CAS, no change,
double checked the chipboard on the ECU looks fine.
also double checked Injector connector voltage.... 12.5v on both pins on all connectors.


also noticed that not getting any O2 volts on the log..... i would switch it out but no one around me has EEPROM ecu.
possible ECU?

im going to take a log and upload it.
as well as swap my 91 engine harness onto it.

please help...! have two weeks to get this thing running.!

 

[95TalonOwner]

Have you checked if you are getting power to the resistor box?

Also, have you checked the plugs at the injectors to see what you get when you are cranking the car over? Oh, just reread it and saw that you have.

At the injector plugs you should have one wire that is a constant + power wire, and you should have one that is a pulsing ground. In your post it sounds like you are saying you have constant power to both pins, which is wrong.

Refer to this post.

 

[Jankenshank]

Refer to this post.

i understand that it is wrong....

whats the cause? whats the solution?

 

[95TalonOwner]

Either the wiring is wrong with the different harnesses or your ECU is bad. If I read everything right, you are still using a 90 ecu with 91-94 wiring for everything else?

 

[rlacasse1]

If you have a constant 12v to both injector pins then something is screwed up bad with the wiring, it wouldn't be the ECU.

Can you draw up a pretty MS Paint picture of how your wiring is run?

 

[Jankenshank]

Either the wiring is wrong with the different harnesses or your ECU is bad. If I read everything right, you are still using a 90 ecu with 91-94 wiring for everything else?

wrong, 90 ecu, 90 engine harness, 91-94 body harness.

If you have a constant 12v to both injector pins then something is screwed up bad with the wiring, it wouldn't be the ECU.

Can you draw up a pretty MS Paint picture of how your wiring is run?

the thing is i didn't touch any wires when transferring shells,

my thought is... it ran before, it should run after.

but sure when i get a chance tonight i will draw it up.

im almost done putting the 90 body harness in.....

 

[rlacasse1]

Hmmmmm. Then that is odd.

Just to make sure, you have a +12v on both pins at the injectors correct?

Because, and I make get the wires mixed up, it's been a while, on the injector plug there is a small wire and a fat wire, right? I can't remember the colors. The fat one should be a constant + wire. And the little wire should be a pulsing ground.

I just don't think an ECU or any other electronic could make you get +12v to both pins. That really sounds like a wiring issue.

 

[Jankenshank]

just got done hooking up 90 body harness....

so all electrical is 90 right now!

IT USED TO RUN IN THIS STATE!

but does the same thing.

crank crank crank....... no injectors.


so i guess its something thats miss connected.....................
going to tear the engine harness out and put a 91 harness on it.....

only issue is that my 91 harness is hacked to bits so will take some time puttin git back together.

any wisemen have any thoughts on my problem...

regards janken.

 

[Jankenshank]

swapped everything to 91...

91 CAS
91 PTU
91 coil pack
91 engine harness.

about to crank....... fingers crossed./...

 

[rlacasse1]

Well, are you back from crankin it yet?

Did it start?

 

[Jankenshank]

cranks over and runs!

but RPM MAX's out! like crank crank crank start 0-8k and hold's

scared the sh*t out of me!

adjusted TPS to read .63v at idle and does the same thing. revs all the way up.

any ideas on how to get it to idle? instead of rev up?

 

[rlacasse1]

Is your throttle cable to tight?

It shouldn't even be able to rev that high unless the throttle plate is open.

 

[Jankenshank]

its a aftermarket TB, with a manual idle screw...

when cranking i move the idle screw (slowly) in until it starts, Links says it stops reving at 3300RPM.

then i go and readjust my Link TPS settings.

 

[Jankenshank]

sorted it all out! CHEERS FOR ALL THE HELP PEOPLE!

<iframe title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/CHD9negcO7Q" frameborder="0" allowfullscreen></iframe>



now running 91 wiring all over!

 

[xjokux]

How did you fix the problem?