Misfire and code 25/26 - need help (1 Viewer)

[ZackR]

Took the hood off today to get a better look at things. The harness seemed to be laying against the egr tube, but there wasn't any visible damage. I moved it out of the way. Started her up and unplugged one plug wire at a time. The miss got worse on every plug except 6. Went through them twice and my wife and I both agree no change on 6, but all the rest made a worse miss. Checked the #6 injector wiring. Good continuity and no resistance back to the ecm and to the battery. Listened to the injector with a stethoscope per the FSM, and it sounds the same as the others... I'm at a loss again... Might need to cut into the harness wrap by the egr to see if anything is melted in there, but since the wiring seemed good to the injector, I'm not sure.

Cut into it and confirm, mine had no visible damage on the outside but was missing insulation on a few of the wires once opened up.

 

[gorbilax]

@Red Merle - I can see the temp readings on Toyobd1/Toyocom and they gradually increase as the car runs. As long as the tool pulls data from the ECT sensor, I think I am good on that front.

@ZackR - once you cut it open, what did you wrap it back up with to protect it from heat?

 

[CruiseLander]

Hello Mud - need some help with my 94 FZJ80. This truck came to me from a family friend who moved out of state. Before I got it, it sat for several years and wasn't driven. When originally parked, it was running fine, but I just got it back on the road a few weeks ago and it has a bad miss under acceleration. I also have a code 25 and 26.

I've replaced plugs, wires, cap, rotor, and changed the air filter, with no change. I also did a compression test (but having trouble tightening the hose on the tester in the deep spark plug tubes, so I don't know how accurate it is). There's no noticeable drop on any of the cylinders. They're all around 170. The p/o replaced the intake plenum a couple of years before the truck came to me, and I just checked it again and it's in good shape with no cracks or leaks. The gas light was on when I got it, and I've since added ~19 gal of fresh gas on top of the little bit of old gas. I've been reading too many posts and pretty sure I'm overthinking everything, talking myself in circles around what to test, and not getting anywhere. Where should I go from here? What's the best thing to test next?

Did you ever get rid of your code?

Mine has been showing 25 and then 26 but not at the same time. I have deleted my PAIR, EGR, and all stuff under upper intake plenum. I did not have any problems with those out for more than 2k miles and then got a CEL randomly. I then got new NTK O2 sensor and moved them up to the manifold with code still coming back. My injectors seem to good as i get a rough idle when unplugging each injector. Tested the VAF on vehicle and it is within normal limits. all vacuum hoses are new expect for big intake pipe which i did not notice any leak.

 

[Desert Dino]

@Red Merle - I can see the temp readings on Toyobd1/Toyocom and they gradually increase as the car runs. As long as the tool pulls data from the ECT sensor, I think I am good on that front.

@ZackR - once you cut it open, what did you wrap it back up with to protect it from heat?

@gorbilax did you fined the problem and solved it?

 

[gorbilax]

For anyone who comes across this post via search, I wanted to come back and give an update...

Life got in the way for awhile, bought a house, was broke, and I had to park her for a few years. Fast forward to 2022. I've found myself with some time and money again, and I'm midway through a head gasket job. Just discovered my #6 injector has an open coil, which is almost certainly the cause here. I can't remember if I ever put an ohm meter on it back in 2019 or not. Either way, new injector on order and we'll see how she runs once everything is back together.

 

[CruiseLander]

My problem ended up being damaged woring to oxygen sensors.