1987 runner

I have a 1987 4 runner 22RE that has been sitting for 6 years. I have cleaned the fuel tank and installed a new fuel pump and filter. I have fuel pressure to the fuel rail and a good blue spark at the plugs but the injectors are not opening. I have power to the injectors with the key on so that tells me the ground is what is being switched. I am concerned about the communication from the distributor to the egnitor to the ECM. I do not know what the 2 wires from the distributor to the ignitor do and if they are supposed to be hot and when. I did check the injectors when I had them out at the battery and they do not "click" and act like a dead short. Replacing them tonight and maybe that's my problem. Any help would be appreciated.

RAD4Runner

Please see my signature for what is probably your problem.
If injectors are all a dead short, they would smoke. Could it be they're just gummed up from sitting idle for so long?

When IG is on, you should get 12V at pins 1 of injector.
Yes, ECU switches the ground via the wires shown in red below. When IG is on, you should get 12V at pins 1 of injector. When ECU pulses, pins 20 and 10 are brought to ground.

Again, see my signature for what is probably your problem

1987 runner

Thank you very much for the print that will be a big help. The wiring all looks good at least from what I can tell and it has not been tampered with. The injectors may be the problem they are definetly stuck. So the ECM is switching the 10 and 20 terminals from hot to ground?

Thanks

RAD4Runner

Yes, most likely gummed up injector. Even if electrical works, the solenoid plunger would not move because it's stuck. That's why you don't hear or feel it click.
There should be a practical way to check for that.
Or speak about it with the professional injector cleaning places (like www.rceng.com) before shipping them.
Yes. Basically connecting them to ground, but just pulses.
So with engine not running, but IG on, and ECU connected, you should see 12V or so at Pins 10 / 20. You'd be reading through the coil of the injector.

1987 runner

Ok do you happen to have a print of the distributor and the ignitor to the ecm in case the injectors do not fix the problem. I believe that's where I will find it. Thanks so much for your help!

muddpigg

iTrader: (1)

Check out flame thrower, he was on site but haven't seen traffic by him lately. I'm currently running his setup and happy with it. He sent replacements so no down time.

I've had injectors cleaned by witchhunter performance - they send a print out of before and after cleaning flow rate and pattern check.

RAD4Runner

92ehatch

Those are low impedence injectors and use a resistor box on the ground side to the ecu. You said you hooked straight to the battery. I know without that resistor box that the ecu will hate you, but not sure if hooking them straight to battery will cause issue.

hooking straight to battery is around a 4amp draw, with the resistor box in place it is only around a .8 amp draw. I do not know if or how that would affect the injectors. (I would think they would be ok if only momentarily attached to the battery)

did you happen to do a resistance check on the injectors themselves?

RAD4Runner

[QUOTE=92ehatch;52385436]Those are low impedence injectors and use a resistor box on the ground side to the ecu...
...hooking straight to battery is around a 4amp draw, with the resistor box in place it is only around a .8 amp draw...
Actually the resistor box is on positive side (here) , but yes, they limit the current.
Four amps versus 0.8 amps is quite a bit of difference.

GreyYota,
Yes, please check resistance of injector coil.

92ehatch

You and your fancy wiring schematics. I need to get those.