Hello all - newb to the forum - thanks in advance for any help

I've got a "new to me" high mileage 300k '96. There's a misfire code for cylinder #1. After checking the plugs, wires, coil swapping - then compression test (looks good) AND sticking a screwdriver in my ear, I suspect the fuel injector.

I tested the #1 plug and power is present. Resistance test of #2 is within spec at 13.9 ohms. However, ohm testing the #1 injector won't move/change my digital multimeter at all. I tried cleaning up the pins with a little sandpaper but nothing. So my question is - besides getting dirty and clogged, can the electrical part of the injector fail? Could that be why I am getting no reading? like the circuit is "open?"

Second question, with a rig with 300k - should I replace all 6? just the one? Thanks again.

If the coil is open then, yes, the injector has to be replaced. Just replace the faulty injector. Install all new O-rings:

Anytime the injector is out of the specified resistance range it is considered faulty. I would replace all at the same time. To save the headache later on


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The big challenge is then finding a quality set of injectors...

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Thanks! I'm using the youtube vids for reference (e.g., Timmy the Toolman).

If replacing just the #1 injector, do the plenums still have to be removed to access the passenger side fuel rail? Am I asking for a headache and skinned knuckles? Or is it just better to take them off and have the more open access?

If I decide to send out the remaining 5 injectors for pro cleaning - is there anything I should do to protect the engine for the week or two while the injectors are being serviced?

I have had fantastic luck with upgraded injectors from Osidetiger. I am running their injectors on 3 of my vehicles, two Yotas and one Honda. A set for the V6 is ~$225. These are stock flowrate so they are completely plug & play and are either Denso or Aisin. The tips provide better fuel atomization since they are a more modern injector design. I expect that sending out for a rebuild of your injectors will cost about the same and if you have one with an electrical fault it may not even be repairable.

I have the upgraded Denso ones from MotorWest Performance out in Cali and they are fantastic. They were around $250 at the time when I purchased them a couple months ago. The job wasn't too hard but make sure you don't drop a socket in the engine when the plentum is out. Also replace the fuel rail gaskets with Toyota ones (strongly recommend a crows foot or an open end wrench to loosen the banjo bolt).

At 300k it is worth the investment replacing all 6 especially if you plan to keep it long term. Wouldn't recommend those "rebuilt" eBay fuel injectors.

Replace the one that is bad. Have them refurbished by this guy Home. It's worth it.

+1 here for the MotorWest injectors. Great service and the 4runner has never run better in my sixteen years of ownership.

Thanks all for your replies. This forum is really helpful.

fwiw - I went with MotorWest Performance replacements so I could have parts on hand as soon as I could find free time (needed it for a visiting relative to use). I also decided at 304k to replace all 6 injectors since they're all the same mileage/age, and like JZiggy said, the rebuild was about the cost of cleaning/refurbishing. Started this morning, found remnants of a nest between the plenums. Took a little more than 3 hours for this beginner. No leaks, no gas smells, no parts left over. Thanks again.

Listen to Spartacus. But instead of needing a guy, be the guy. Invest in a $60 tool no dealership wants the public to know about. Non dismantle injector cleaner. Hooks directly to your service port and compressed air. With a reservoir for the cleaner to be blown through while running engine. They come with pressure regulator attached to run the proper pressure. It's compatible with pretty much any vehicle I use it on all mine. Never had injector issue even on my 94 xj. Still spraying in perfect form.. if you have other cars I'd recommend it!

I'll deffo check that out! This time, my problem injector was shorted out so I think cleaning wouldn't have fixed it, but next time for sure

No definitely not that one! My 2010 only has 100,000 miles on it. Original owner. I use it as a preventative measure like every 25,000 miles to avoid any issues from ever happening in the first place there and the additional wear and tear involved in that situation. Also maintaining optimal engine performance protecting so much more than your injectors from more carnage. Good work on the repair! ✌️👽

have not heard of this tool. got a link ? used it on a 3rd gen 4runner ?

I use something similar to this at work: Car Fuel Injector Cleaner Tool,Non-Dismantle Fuel Injector Cleaner Kit with 600ML Tank,140PSI Fuel Injector System Cleaning Machine with Portable Case For Petrol Cars https://a.co/d/adtUZIu

Keep in mind you will need to disable the fuel pump by pulling the fuse, tap into the fuel rail, plug the fuel rail return line, and then run fuel injector cleaner designed to be ran through the fuel rail directly while the engine is running. We use MOC fuel injector cleaner kits at my work (gm dealership).

It’s worth pointing out that fuel injector cleaners usually only cover the cost of the cleaner if an injector fails during or after cleaning (it’s happened to me and possible) and that you are only cleaning the internals that touch fuel. It will not fix a bad fuel injector solenoid/driver. If the fuel injector is too clogged then the cleaner can’t flow to clear the blockage either.

Considering our fuel system I would recommend using fuel injector cleaner additive that gets added to the tank vs using a fuel injector cleaner tool at the fuel rail. Newer vehicles are manufactured with fittings on or right before the fuel rails which make it a lot easier to use the fuel injector cleaner tool.