Multiple cylinder misfire codes

Did they test at the injector or the ecu? Fishing out problem wires is annoying but usually just a quick soldering in a new wire will do the fix. Was that shop that reputable of a place?

 

They tested the injector, and they have good reputation years of experience. But still I'm hopping it's not the ecu. Are there some tests I can do before paying 1k+ for that fix?

 

I like to question people's work so maybe try this advice. I'm assuming your injectors work like mine. I never stuck my head into the wiring of the 4.0L motor. So far they are saying cyl 5 is the issue? Get them to show you the issue. You need to know what they know so you can be able to follow their explanation.

Put up with me here because I may drop some stuff you may know, but I want to make sure we are all on the right page.

If they have enough time for you. I'd ask them to show you the problem. The old school way is they have some light bulb thingy that plugs in place of the injector. (Multimeter works too) When you crank over the motor it should blink. What they are telling you cyl 5 isn't blinking and other cylinders are blinking. What does this mean? Bad ECU? Or an open connection in the wire.

Open connection in a wire is cheaper than an ECU. The way an injector works is power is pushed to it when your truck is in ON and START. Power passes through the injector and out to the wire to the ECU. The ECU closes the loop and causes the injector to pulse. There is a possibility of an open connection before the ECU. See if they pinned out the cyl 5 injector wire going into the ECU.

You can test continuity through the wire that goes to the ECU. That shop could show you in a few minutes or someone with a multimeter. It would be a bit hard to do this without a buddy. BE VERY CAREFUL around the ECU if you don't know what you are doing. Doing something careless will fry it.

To answer your question if all this made no sense. Yes this one last test that could be a saving point before needing a new ECU. Hope this helped

 

I checked the wire that comes from the ecu to the injector 5, right from the ecu has no pulse.

 

Ouch

 

Is there a pulse coming directly out of the ECU without the wire hooked up? If so, it's the wire. Otherwise, ECU time...

 

Replaced the ecu and still have same problem!!

 

Thanks for all your help mike, truck is back running! Its wasn't the ecm, I had to unwrap all the wires at the engine bay that came from the ecm and found the problem there. Redid the wiring and truck roors back again. I couldn't get my money back from wreck yard for the ECM but got the 200 bucks on credit on their place, so when ever I need something for the tacoma I can go their the good thing is they have 4 tacomas their so they have almost every part I could need. So final repair was some wire I had already so thats a total of $0

 

Hell ya, Damn told you it was a wire. Sucks you had to buy a used ecu. I get a few wire gremlins all the time in my truck. Glad your truck is back to working

 

So how do you check the wires coming from ECM - I now have a multiple cylinder misfire in 5 and 6.