ahickman

Did my search, but did not find the info I was hoping for. I have pulled the injectors from an 86 22RE and tested each using an ohm meter and a +12V supply. All four ohm out at 3 Ohms or so, but only two of the four sound like they work ("clicking noise" when applying +12V). Before pulling the injectors, the engine ran reasonably well but rich. Any suggestion on how else I can test the injectors other than sending them off to Witchunter?

abecedarian

all four injectors are fired simultaneously by the ECU and all 4 fire once per crankshaft revolution.

Does that help?

ahickman

Abe, not picking up on the hint I guess. I am assuming that the two that do not actuate (e.g. make clicking noises) when 12V is applied are either frozen or faulty. Would you agree? Last 10 injectors I tested (4 from 22RE and 6 from 3VZE) all made an audible clicking noise as I succesively tapped the lead to 12V.

abecedarian

the injectors are wired in two 'banks' with each bank comprised of two injectors.
external to the engine (i.e.: in the wiring harness) the two banks are wired together creating one bank of 4 injectors.
make more sense?

abecedarian

were the injectors saturated or peak-and-hold?

ahickman

OK, I definitely understand the wiring and firing sequence for the injectors, but don't know that this helps identify whether the two injectors are faulty. Not sure that I know how to identify the two types of injectors. Always thought that an injector was simply a coil/solenoid that moved a needle or plunger when energized.

vital22re

iTrader: (2)

why not have an injector place bench flow test the injectors? It'll let you know if they are stuck open or clogged or whatever. Clean injectors are awsome.

ahickman

Just getting back around to this this thread. Buttoned up the 22RE using the suspect injectors. Ran rough, but did idle. Pulled each plug wire and found that #3 makes no difference. Good spark to the plug, so I took out the sparkplug and replaced it with a new one from the shelf. Ran rough still, so I took out the plug and noticed it was not wet or had not the faintest smell of fuel. Before I take apart the plenum and fuel rail, would anyone disagree that the #3 injector is bad or alternatively is not getting a 12V pulse? I should be able to verify the pulse signal with an LED by tapping into the injector harness, correct?

Wile E. Toyote

it's tight to get to, but switch the plug on the injector with another and see if the dead hole moves. If it does, electrical problem, if not: injector problem.

ahickman

Sure is nice to have someone help me think "out of the box". Thanks.

Wile E. Toyote

lol, unfortunately I had to learn a lot about testing the FI system.

ahickman

Still going at this! Pulled the plenum, fuel rail and injectors. Re-verified that each injector was working by +12V supply. Also visually looked for spray at nozzel. Even the suspect #3 injector seemed good. Reassembled and swapped the suspect injector to #1 port to see if the problem followed. Also swapped the #2 and #3 injector leads per Wile E. Toyota suggested. Figured if it was the injector, the problem would now be on #1. If it was the electrical feed to the injector, then the problem would be on #2.

I cranked it back up and it still ran rough. Pulled the #1 ignition wire and it died out. Pulled the #2 and it died out. Pulled #3 and made no change, just ran rough. Pulled #4 and no change. So the problem is not fuel injector or lead connector.

Confirmed that spark was present on #3 wire by holding it to the block. Good spark, but makes no difference when plugged back in.

I am confident that the head and valves on #3 are OK and adjusted, having just pulled the head to replace the HG.

Suggestions....Please!

ahickman

Anyone? Bump!

Wile E. Toyote

have you done a compression test?

TOYOTA 1

I'm having the same problem but on cylinder # 2.

when you tested the injector plugs, was there power to both sides of the plug?
if so i think thats my problem

ahickman

Wilie, yes I have done a compression test. 160 +/- on all four.

Toyota1, if you are seing +12V on both leads to the injector, that is expected. I think the ECU pulls on lead to ground to fire the injector.

4Crawler

iTrader: (3)

Check the injector wire splices that live about 6" up inside the wire loom. There are 2 splices on the ground side, #2 and #4 connect together at one and #1 and #3 connect at the other and then those two wires runs back the No10 and No20 connections on the ECU.

TOYOTA 1

no im not, im only getting power to the one side of the plug, and the wires look good.

ahickman

4Crawler....will do. Not lookin forward to pulling the plenum again

ahickman

Success! Removed the TB and pulled off the electrical tape and wire looms. Found that the ground wire on #3 had started to oxidize and all but two or three copper strands were conductive. The ohm meter showed continuity, but I could feel a buldge in the wire close to the injector cap which led me to cutting the wire back and exposing green powder and a few black wires. Cut the wire back to where it was good copper and then soldered in a new pigtail. Assembled everything and fired her up. Purrs like a kitten! Thanks all!