4.7 Fuel Injector Replacement

[natevans65]

Ok, 04 V8 with 225k miles. Was thinking of replacing all 8 injectors. Why? 13 year old truck and my thought process was that from a maintenance perspective at $35 each (reman) I could replace all 8 knowing that all 8 would be new delivering fuel as advertised. Symptoms: slugish, just replaced all 8 plugs, I clean the throttle body every 20K miles or so and I just replace things as time and mileage continue to ever increase. Do you know of any quick/easy ways to test the injectors to see if in fact all all working properly? From a military maintenance background we would have to replace parst/components on the helo based on hours flown so that is part of my maintenance thought process when i look at mileage and time on the v8. I tend to do preventitive prior to an issue vs being faced with a problem now. thank you for your input.

 

[skott]

My 2 cents....I wouldn't replace injectors unless you know you have some bad ones. Get a scan tool that reads live data and look at fuel trim settings to get an idea of whether fuel delivery looks good. As far as testing them, the only suggestion I have (without having to remove them) is get a fuel pressure gauge and see if they hold pressure--this could see if you have any that are leaking.
Typically, a bad or failing injector will result in a misfire that you can hear/feel.

Ayways, just my opinion. I love my 4Runner, but I don't think using the same maintenance approach you do on a helicopter applies

 

[unevolved]

I agree with checking fuel trims. If you're going to replace them, though, I'd go OEM for injectors, or at least a known-good manufacturer. Injectors aren't a common failure item on Toyotas, and will likely last as long as the rest of the truck if you feed it good gas.

There's no test for injectors that doesn't involve them coming out of the car, if they're not working symptoms will show up elsewhere (like fuel trims, as previously mentioned). You could pull them out and have them rated (pressurized supply, hold open, measure flow) to check functionality, but other than that I wouldn't worry about it.

 

[ZiaMan]

Have you tried a fuel cleaner like Chevron Techron, Redline SI-1 or Libe Control Fuel Plus?

 

[duffdog]

Ok, 04 V8 with 225k miles. Was thinking of replacing all 8 injectors. Why? 13 year old truck and my thought process was that from a maintenance perspective at $35 each (reman) I could replace all 8 knowing that all 8 would be new delivering fuel as advertised. Symptoms: slugish, just replaced all 8 plugs, I clean the throttle body every 20K miles or so and I just replace things as time and mileage continue to ever increase. Do you know of any quick/easy ways to test the injectors to see if in fact all all working properly? From a military maintenance background we would have to replace parst/components on the helo based on hours flown so that is part of my maintenance thought process when i look at mileage and time on the v8. I tend to do preventitive prior to an issue vs being faced with a problem now. thank you for your input.

I do not know of any way to check the actual flow of injectors without removing them, sending them to RC racing and getting them flow balanced. Also, remanufactured injectors are definitely not what you want if you wish to restore performance. I am not sure how exactly a remanufactured injector can be flow balanced unless every single one of them is tested. My bet is that reman injectors are slapped together in China and thrown into a box with absolutely no guarantee to their performance. New, unused factory injectors are the only thing I would use unless you plan on supercharging, in which case you would want new custom injectors.

 

[natevans65]

Well, thank you for the input, I think I will look for another project to tackle!