Captaincurt33

Hey , new to the forum . Long time yota lover. Looking for some advice on how to fix my issue .
Only injector 1 and 3 are getting pulse so the truck only runs on 2 cyl . It's a 1996 4runner 2.7. I just put the motor in with the exsisting harness . My old motor worked perfect with 250000km until I sucked in a bunch of water while in the mud pit. I've tested each injector and they all work. I took the harness off and visually looked for any spliced or broken wires . There's no pulse at the harness plug for injector 2 and 4 . Been trying to figure this out for a few days and can't seem to get it . Maybe there's a common problem for this that I don't know about ? Or ? Hopefully someone can help me

rokblok

iTrader: (1)

Common grounds? Check ALL ground splices and eyelets.

Captaincurt33

I've checked grounds but I'll double check using the manual making sure I got them all correct . Also fuses are all good.

rokblok

iTrader: (1)

I don't have my 3RZ FSM with me at the moment. I can't remember exactly where the injector common grounds are located. It's inside the engine bay harness though. And I don't remember exactly where they reach an eyelet to be final grounded. You have a good, sufficient ground cable from the body to the block and from the block to the battery negative, right? ( I ran 4ga grounds and 2ga positive to my starter. Silver soldered lugs on the ends, insulated with heat shrink.)

I believe there was a ground eyelet under the coil packs, on the coil pack bracket, and one on the front(towards radiator) of the intake manifold, and I think there was one somewhere else. But these had 3-4 brown ground wires coming to each one.

Give me a couple of days and I will get my FSM and locate the ground points.

Captaincurt33

Thanks for the info. I have all the grounds you just described. I'm not at the truck right now but I know there's 4 brown wires going to a ground right near the dizzy . I don't have separate coil packs in the 96.

I'm gonna test the ecu Pinout with the noid light . Then for sure ill know either the ecu is sending pulse and the circuit is being messed in the harness somewhere? Or maybe my ecu isn't sending pulse anymore? If it is sending pulse ( still should be I never did anything to the ecu ) I'm going to wire the injector up right to the Pinout and that should work? I know it's prob Not the best way to do things but I need my truck up and running

I went to Toyota and they printed me out all the wire diagrams and pinouts so, hopefully I can get it to run on all 4 today

rokblok

iTrader: (1)

Sorry, wasn't paying attention to the year... Oops.

Let us know how it goes.

Iirc, the intake manifold grounds are the ones for injectors. I don't remember if they get key on 12V and ECM supplies ground, or vice versa. A diagram will tell you though.

Captaincurt33

Got busy, took a few days off from working on the 4runner. Looked at it today and what I did was , I wired up the injector pulse wire for cyl 1 and 3 right from the ecu plug to an injector and it worked great. I then switched the pulse wire to the ecu pin for injector 2 and 4 . When I put it on the ecu Pinout for injector 2 and 4 it didn't pulse. Making me believe me ecu is shot? So short form . Ecu Pinout wire for injector 1&3 pulsed and 2&4 doesn't pulse at the ecu.

This indicates that there's no shorts in my harness and my ecu is bad? It's hard to find an ecu around here so it may take me a while to know for sure

Captaincurt33

Also I'm not sure if there are any other factors that would make the ecu not work properly. Especially if I can get the truck running on 2 cyls but no pulse only 2 injectors? Someone ever have this problem in a 3rd gen??