Anyone know what the average cost of a fuel injector cleaning is for a 99 3.4l 4runner Sr5? It is my last ditch at improving my sub-par 12.5 MPG problem. Do most local mechanics perform this?

Also, thinking about the PCV valve, maybe replacing it...is this a simple thing to do?

Also, I have heard that using a "high-flow" airfilter might help Gas mileage...is this referring to the K&N or Amsoil filters only? Are there disposable "high-flow" airfilters and is the nature of such filters that they are disposable.

I am at the end of my rope with this runner...thinking about selling it due to the terrible Gas mileage...I hate filling up all the time when it is on E with only 185 miles on the Odo!

 

Run a can of Lucas fuel treatment in the next tank of gas, and buy a good reusable filter. You clean those filters every 1500 miles, or so, and they work as good as new... I am getting ready to put the Amsoil in my truck... how many miles on your truck?

 

Run a can/bottle of any good injector cleaner and you should be fine. As for the mileage, yeah, that's pretty crappy. You might want to clean the MAF while your at it and no jackrabbit starts and take it easy on the gas pedal.

 

I have used several injector treatments including LUCAS. All to no avail. I have made sure to only use ones that would not leave residue in the injectors, which I understand can create more issues...however, even after all the following items my mileage has still decreased from about 14 mpg to around 12.5:

Spark plugs (denso)
Wires (OEM)
Fuel Filter (OEM)
Seafoam (in gas tank and through PCV)
TB scrubbed and cleaned
MAF (cleaned as well as I could and very carefully, did not look damaged in any way)
LUCAS treatment
Valvoline treatment
Tire pressure check
New OEM air filter

My concern with a high flow air filter is the maintenance of the air flow system, I have heard bad things about them allowing junk through and especially the MAF getting very dirty

The specs on my truck in a nutshell are 1999 SR5, 136k, stock wheels.

I am desperate at this point to get my mileage in the mid teens at least especially with gas prices escalating the way they are. I would hate to have to sell the runner, we just bought it in November for my wife who has always wanted one, but it is costing us an arm and a leg to fuel it plus try to determine what the issue is!

Thanks for the input on all of this...would an oil change perhaps help? It is not due for one yet...would it be worth it to try to switch to synthetic oil. i suppose I could ask my mechanic to flush the system on the next oil change and run synth in this time...however, the research I have done says that at the mileage it is at I should just stick to what it is used to...I see some truth in this, but am not wholly convinced.

 

Someone mentioned replacing the PCV valve. How can I test mine to see if it is defective?

I DID put Seafoam through that valve, could that have damaged it?

Is it a pretty simple replacement?

 

I sent mine (22RE) out to RC Engineering, ~$25/injector w/ 3 day turnaround time. Cruzin Performance is another place that does it for about half that cost, links to both below:

http://www.4crawler.com/4x4/CheapTri...html#Injectors

 

Give redline fuel system cleaner a try...it's worked for me in the past only one i've found that kept the injectors crap free for a while

 

Thanks,

I forgot to mention, I also have used Redline. All in all, since I bought the truck in November I have used Lucas, Seafoam, Redline and lastly Valvoline through the injectors. All to no avail in terms of improved performance, actually I have seen mpg drop. Could I be doing something wrong? I have spent way to much money on FI cleaners that have not worked in terms of improving GM...need to find a for sure fix at this point.

Thank you.

 

do a search for BG44k or something like that. Supposedly you get it from the dealers.

Good luck, as I currently get about 14 mpg with 4.88's and 33's but only 90k miles

Gonna do everything you did maintenance wise in a couple weeks.

 

I like the Amsoil PI fuel treatment.It should maintain the injectors to be clean all the time.

 

I don't think there is anything you can pour into the gas tank that will clean the injector as well as a shop can do. Maybe the only thing close would be the kind of cleaner that you connect directy to the fuel rail and run the cleaner straight, I think MotoVac is one such system. The shop cleaning is nice as they test the injectors prior to and after cleaning and they also balance them so they all put out the same amount fo fuel. With the printed report you get back, you can see the before and after results.

 

BG 44k works great used a few months ago cleaned fuel system well.

 

With all the fuel system cleaners you've been using, you might want to replace the (front) O2 sensor. Some folks have reported that the O2 sensor has been getting gummed-up after running things like SeaFoam.

Also check the plugs for the same reason.

 

Cleaned mine at Cruzin Performance. . Went from 28 mpg to 31+ mpg on highway. 22rte 86 5 speed. He said they werent that dirty but 42k on an old truck I figured it wouldnt hurt. Aboput 2 or 3 mpg better in city also.

 

Yeah, if you have roughly stock size tires, that mileage sucks.
I get an avg of 20 in my 98 (w/3.4 & auto).
I would say the O2 sensor is suspect also. Try pulling it and cleaning it real good w/ some electronic parts cleaner.
If you think it's bad, I have one I bought for my Runner when I got a CEL, but after playing w/ the connection, the CEL went away. I'd be willing to sell it for a little less than I bought it for (from Gadget).

You could also try removing your roof-rack crossbars. I plan to try that to see if it helps my mileage any.

 

Don't worry too much, I have the same rig as you and get the same crappy mileage. My drop in mileage occurred after I "seafoamed". Before = 230 miles before gas light. After = 195. I have done everything your have except for the fuel filter which I have in my garage to put in this weekend. For the PCV replacement, it's a $10 part from the dealer that takes about 30 seconds to put in - no tool s needed. Just pull the old one out and shove the new one in. What part of the country do you live in? I was wondering if the gas I've been getting might be having an effect. I'll keep you posted on the results or if I find the cure..

Oh yeah, I also replaced the front o2 sensor.....

 

And less than that from Schucks or Napa.


This is true as well... I think we're still in "Winter Gas" until late April(?).

 

I'm so luck I have a friend that works in a diesel pump/turbo shop. I can pull my injectors out and have them back to me 10hrs later good as new for the best price of all FREE. So If any of you guys know of or can find a injection shop in your area this may be good place to go for quick service.