Pete1122

I swapped my injectors on my 1989 3.0 for some flamethrowers and after the install found that I was getting a misfire on cyl 3 and 5. When I pull the plug wires the engine makes no change in idle or sound, it is shaking really bad. So I changed the injectors 3 and 5 out for new ones, put everything back together and have the exact same issue.

I decided to pull the spark plugs and replace them with new ones just to help eliminate all the things I could think of. Still no change, Cyl 3 and 5 are missing.

Can anyone think of anything else that could be the problem? I am at a loss.

Recap:

1. Truck ran great
2. Changed Injectors/ Truck misfires on 3 and 5
3. Changed injectors 3 and 5
4. Truck misfires on 3 and 5
5. Changed spark plugs 3 and 5
6. Truck misfires on 3 and 5.

rustypigeon

Check the wiring. The injector connector has two wires attached to it. The black wire with a red stripe should have positive battery voltage going to it when the ignition is on. The white wire with a red stripe should give you a pulsing ground signal when the engine is cranking and running. This can be checked with a computer safe test light if you have one.

You likely have a bad splice in the wiring. All the injectors splice together on the positive voltage wire. Cylinders 1,3,5 splice together to ECU terminal #10 for the ground signal, cylinders 2,4,6, splice together to ECU terminal #20 for the ground signal.

Pete1122

I hear what you are saying with the wiring, however the only thing I changed was the injectors, I'm pretty sure my connections were put on right. Also Cylinder 1 is still working just fine. Would you suggest pulling the plenum again and checking the injector wiring?

rustypigeon

When you changed the injectors the second time what did you put there? The original injectors? Flamethrowers?

Pete1122

Two new flamethrower injectors with new wiring.

rustypigeon

I think the injectors are not firing properly on those cylinders. Spark is easy to check, but I don't think that would be the likely problem since your other cylinders have spark.

The problem could be the injector, or it could be the wiring to the injector. You won't know unless you diagnose it. The new injectors may be drawing more amperage making a corroded or loose splice apparent.

What was wrong with your original injectors?

Pete1122

Nothing wrong with the old injectors, I was putting new valve cover gaskets on and decided to swap injectors while the plenum was off.

Pete1122

I took the Plenum off again, all the wires are wrapped and nothing looks spliced or out of place. The injector connections are on tight and the injectors rotate freely as they should. I did notice my cold start fuel line attaching to the fuel rail was a little loose causing some fuel leakage. But I cant imagine that was the issue. I'm not sure what else to do while I have the Plenum off to troubleshoot this.

I dont really want to pull the fuel rail again to remove the injectors because I dont have extra crush washers for the fuel lines.

rustypigeon

You dont have to remove the injectors to check the wiring. Did you check them like I said in post #2? It only takes a couple minutes with your multimeter and computer safe test light. You can't diagnose a car without these tools. The factory splices are buried in the harness and often corrode. You may have to do a voltage drop test on the wires if there is corrosion in the splices.

If nothing else, listen for clicking noises from the injector with an automotive stethescope or a screwdriver handle against your ear.

Pete1122

I unwrapped all the wires and verified that the splices looked good. I then tested with my multimeter and found that each injector is getting 12v. I also tested the OHM readings, they all tested good.

I am unable to do the stethescope to the number 3 and 5 injector because they are buried under the plenum once I put everything back together and start it.

Is there any way fuel could not be getting to injector 3 and 5 but getting to injector 1? I'm lost.

rustypigeon

Did you check the ground signal? A 194 bulb with its base wires straightened out can be used as a noid light to check for pulse.

Catcher5

My Toy is not firing on two and three
There is spark it starts and idles
Has no power. New cap rotor wires plugs igniter coil injectors. If I pull two and three no change.
If I put a screw driver on the injectors to my ear I hear all the injectors clicking.
Can it be the knock sensor or temp sensor?

Pete1122

I verified with a Noid light that all injectors are good. I tightened everything, threw the plenum back on and now just cyl 5 is not firing. Cyl 3 works just fine. I'm not sure what to make of that, I sprayed some carb fluid around to try to identify any vac leaks. Once I get home from work I'm going to crank down the Plenum bolts to ensure everything is torqued correctly. Could a vac leak cause this? I feel like I'm chasing shadows now.

Fundy Rider

Had a similar issue with a 22re after a head gasket and a whole whack of new parts including the flamethrower injectors.


Pulled a lot of hair out not even thinking it could be the flamethrower injectors. A month later after trouble shooting everything else I threw in the original Toyota injectors and she purred like a kitten.


Give it a shot it worked for me.

Catcher5

So you think it the injectors huh. So maybe the three hole are requiring too much fuel?

Fundy Rider

I really can't say for sure. I had similar issues and going back to factory injectors cured my miss.


I don't want to say it was the flamethrower injectors themselves. I still want to try them again. I cleaned my fuel rail and all of the intake. I may have not got all the crap out and may have clogged #1 and #2 up. Remember I have a 22re.


I am just saying why not eliminate the possibility of it being the injectors if you know the factory ones were working.


Myself I would like to send both sets out for a cleaning and to be properly tested to reveal what happened and not guess.


I live in the Canadian East Coast and can't find a place to do the work I want but am a mile from the Maine border. Anyone know of a place where I could send the injectors out to be checked and cleaned?