91 3.0 Fuel Injectors Not Working?

[lonecountryboy]

So I have a 91 runner with a 3.0 in it with a no start condition. I have checked fuel pressure and spark. both are good. I can squirt some fuel in the throttle body and it will run until it uses it up. Put a noid light on an injector and no pulses. From looking at the print it looks like that pulse is coming from the ECU? So any way to check the ECU for proper function I can't find anything on the web. Has this happened to anyone? I have verified the grounds are all good and there is spark and fuel pressure but Injectors are not firing. Also there is 12V on one side of the injector which from the prints is supposed to be there so looks like the ECU but before I go through the trouble of finding one I wanted to make sure I checked everything I could before I did that. Oh and the cold start injector does work I had it out and watched it, it is spraying on cold start. Any suggestions ?

 

[Ahlem]

I had a similar condition and solved it by pulling each fuse individually and reinstalling them. I also pulled and reinstalled the relays. I think the aging connection between the spade terminals and the receptacles just got a bit corroded in my case. I couldn't tell you which one did the trick but I used contact cleaner and some electrical grease and haven't had that problem since.

 

[lonecountryboy]

Well I did find something interesting, which I posted in another thread. Somebody relocated the knock sensor to the lifting hook on the drivers side. It is not a toyota KS and I don't know which manufactures it is, but it was broken and more than likely grounding out. So would this cause the injectors not to fire?

 

[CentCalKid]

You have a 2nd Gen? Holy s*&t...what were you thinking?

 

[flyinhawaiian01]

Well that was a pointless post...


Anyways, there is a resistor pack on the fenderwell for the injectors to fire, check that before anything else.

As for +12VDC at the injectors, that is correct, they are triggered with a negative pulse from the ecu. Check the resistor pack and all of its connections before screwin' with the ecu.

And just an fyi, I don't recall the cutoff year for toyota changing the injectors out and eliminating the resistor pack, it depends on which injectors you have.

If they have a p/n of 23250-65010, you will have the resistor pack. If you have the 23250-65020, those are high impedance and do not require the resistor pack. I think they started using these in '92, but don't quote me on that.