DanStew

I am chasing down the cause of my #2 injector woes. The history. Truck ran fine until 4th of july, i had a bad miss. I pull plugs and #2 cylinder is not firing. Has air, and spark, but injector not firing. I drive truck again the injector is firing (veryfied with listening device) A few weeks later it happens again. I read up on possible causes. Right now I pulled the intake and am cutting into the wiring harness looknig for bad splices since the 4runner is an 86. I find the splice for the blue wires. I cut into tape and shocked to see how good of condition the splcie is. It looked brand new. So as of now my question is.

How far down is the splice for the wire wires? I at first thoguht it was going right to Computer but the whites splice together also. So i have cut the harness down quite a bit but havnt gotten to the splices. I am interested to know how far they are so i can maybe skip a cutting the jacket of some of the harness.


Also another injector question. If an injector got plugged or gummed up, will the injector still "tick" or will it be dead and silent? If I do not find a bad splice here i am going to pull injectors and have them rebuilt.

Thanks for any help!!

iamsuperbleeder

I'd blame a 24 year old injector before the wiring, if the wiring looks like it's in that good of shape

were it me, I'd move that injector to a different cylinder, and see if the problem follows that injector

if the misfire follows the injector, then it's the injector going bad; if the misfire stays at cyl 2, then it's the wiring

DanStew

I probably wont get that far. I will probably pull all injectors first and get the rebuild done on them. Pulling the intake and everything twice or more to swap around injectors will just take forever. I still want to inspect the other splice to make sure so i have peace of mine when it comes to the harness. I am happy how it looks so far.

thanks!

iamsuperbleeder

that's a good route too

check out WitchHunter; they do good work

DanStew

Yup THey did my last set when i rebuild the 89's motor. They will be getting my business again

DanStew

Update. I found the other splice. Still didnt look bad but i am gonig to solder them together. I pulled my injectors and found them to be a real mess. #3 injector that wasnt a problem had nasty crud in the filter of the injector. So they will be off tomorrow to witchhunter.

Lysmachia

Keep us posted on how this pans out. So we can name this thread with the answer for search-ability- with the answer!!!

DanStew

Sure. Also hopeing this will cure my little issue of hard starting if i let the truck sit for more than 3 days. It will crank and crank and crank but wont fire untill i pump the heck out of the pedal to get it to take. It will be alive again soon

TOYOTA 1

i had the same problem in my 86 4runner. the wires and the splice looked great, but the inside of the wires were corroded so bad that they weren't carrying current to the injector. i fought with it for ever, i figured it out by using a test light, i tested the wires about every inch until i found the bad spot. good luck!

cman1

iTrader: (1)

im having the same exact issue,#2 and everything!! did injectors fix it?

DanStew

Yup my injectors were the issue. I had one that was going out or rather clogged.

cman1

iTrader: (1)

I changed mine too and am still having the dead cylinder blues........

Hadmatt54

The injectors on a 22re batch fire, which means all 4 injectors fire at the same time. Common thought is that 1&3 fire together and 2&4 fire together, but No 10 and No 20 are tied in the harness after they leave the injectors, so if the ECU completes the ground circuit through either No10 or No20 all four injectors fire. The only places you might have a wiring issue is on the voltage feed between the splice and the injector clip, on the injector clip or on the first splice past the injector where it ties to #4 injector and No 20. Quick test is with the engine off, turn the key to the on position and check voltage from No 10 and No 20 to ground at the ECU. There should be Battery voltage on each one.
If that's what you read there is nothing wrong with the wiring. I had a miss on my 5m-ge in my truck one time and it was the connection at the injector.

cman1

iTrader: (1)

i had to remove the plenum again cuz i damaged an o-ring replacing my injectors.im going to get into the harness today,ive put the fuel rail back on but it seems i read somewhere you have to disable the fuel pump if your going to put power on with the plenum off,is this correct? and as far as finding power in the harness,i should be able to use a standard 12 volt light tester on the harness at first to check for power,then work my way up to the injector connector from there...correct? i REALLY dont want to take this apart again. its getting too friggin cold!!!

natetru

ok, you have got me this far.... my #3 cylinder doesnt fire. compression is good, spark is good. i have good voltage at NO 10, but 0v at no 20.....please help me... i have checked the resistor and it has batt voltage also.... is it time to check the splices?

snow walker

I would check to see If you have power at the injector driver on your passenger side fender well. It's a finned metal box with 2 plugs. 1 plug goes to the fuse box next to it. The other has 1 yellow wire and 1 blue wire. These wires fire your injectors. The blue fires 2 injectors the yellow fires the other 2. You should have a pulsating voltage when running. If you have voltage coming out but no voltage at the injector then I would check the harness.

natetru

ok, will do

Hadmatt54

The injector driver circuitry is totally housed in side the ECU. The finned box you describe is not the injector driver, it is the injector resistor. It is required because the injectors in a 22re / 22rte up until mid 88 were low impedence. Injectors after mid 88 the 22re had high impedence injectors:
This is from a Toyota Manual.
"Low resistance injectors which typically range from 2-3 ohms @ 70F are used with an external resistor in a voltage controlled driver circuit. Low resistance injectors are also used without an external resistor in a current controlled driver circuit. High resistance injectors which typically run 13.8 ohms @70 F do not require the use of an external resistor in a voltage controlled driver circuit."

The 22rte batch fires 2 injectors at a time. #10 and #20 are not tied together in the harness. The 22re however is not wired the same. As I said in my previous post "#10 and #20 are tied together in the harness, so the 22re batch fires all 4 injectors at the same time".

Natetru: If #1, 2 and 4 are firing then the splices where all the wires connect together are ok! (The reds are tied together and the White #10 and #20 wires are tied together. First your problem was with #2 and then you changed the injectors now it is #3. Did you have your injectors reconditioned or are you just using injectors from another motor?

I'm still thinking that you have either got a bad connection at #3 injector (red wire or white/? wire) or the injector is faulty.

natetru

thank you for the help, i didnt start the post. my problem has been at #3 from the beginning. i dop appreciate you taking the time to pass on this info. faulty injector causing no voltage at ecu terminal No 20?

snow walker

Hmm thanks for clearing that up. You learn something new every day. I had no idea that the 22rte engine harness was different than the 22re. My friend is running a 22re engine harness on his rte. The rest of the harness is from a turbo truck. This must mean that all four of his injectors are firing at once. I wonder why Toyota did this.