Unsolvable P0171 'System Too Lean' Code

don't buy from the Stealership

$158 Genuine Toyota 22204-21010 Internal Air Flow Meter

http://www.amazon.com/Toyota-Genuine-Parts-22204-21010-Internal/dp/B0099AQMBI

Genuine Toyota Parts - Meter Sub-Assy, Inta (22204-07010)

http://www.amazon.com/Toyota-OEM-22...8&qid=1461604848&sr=1-15&keywords=22204-07010

looks like the 22204-21010 and 22204-07010 may be interchangeable or one is a replace? Double check your part # and look on Google or a Toyota parts site

 

That dealership (the one I bought it from) is a few hours away unfortunately. BUT I did also get the extended warranty (60,000 miles) from Toyota since the truck has such low original miles, and turns out it's covered under that, so I'm good.

If it hadn't been covered I for sure would have done it myself for much less $$$, seems crazy they would charge that much for a simple plug in repair. Thanks for the help guys

 

Thats good it is covered! But for future reference if it needs replacimg again look up the denso part number on Amazon and get it on there, much cheaper. Denso is the original manufacturer of most electrical parts on our trucks. Then youre not paying for the toyota box!

 

*sigh*

The saga continues Figure I'll just keep updating this thread rather than start another one.

Truck threw the code again today, one day after I got my MAF replaced by Toyota, so I assume its the same pesky P0171 'system too lean' code.

I'm really starting to think this is because my truck lacks the 7th injector kit with the supercharger. I'm still under warranty both with the repair they just made and with the ext. warranty so I'm going to take it back tomorrow and see what they say. Other possibilities may be dirty/bad o2 sensor or a bad catalytic converter.

One reason I'm not so sure it's related to the 7th injector is because I don't ever hear any spark knock or engine pinging, which is the primary reason people opt to install it. Anyway I'll run it by the service techs and see what they think. I'm hoping that's not it though because I highly doubt my warranty will cover the installation of a URD 7th injector lol, but one can dream.

I don't expect anyone to have any advice other than what's already been posted, this is more just me keeping y'all in the loop and venting my frustration, lol.

 

I was thinking of running a 5th injector kit on my 2.7 4cylinder but was told since I've got higher flow injectors (pink) I don't need a 5th injector . Plus being in Calif I'm under the impression that the 5th & 7th injectors are not smog legal

 

Technically, that's true. URD advertises the 7th injector kit as being for "racing cars only", because in some states like f*$@ing California it isn't allowed. But from what I've read, any truck with the kit installed will pass the smog test just fine; it's the visual test that will get you if the inspector catches the 7th injector and decides he doesn't like it. Which is stupid considering it passes the emissions test.

Anyway yeah, I'd much rather avoid that potential headache. So you haven't had any trouble with your truck throwing a lean code with the supercharger installed and no URD kit? I know we have different engines but this gives me a bit of hope that I'm just dealing with a bad o2 sensor, or possibly a bad cat which should be covered under warranty. Seems odd though that a truck with only 25,000 miles on it would have a bat cat already, though it is 12 years old (and likely sat for long periods of time).

 

Passes smog check with no problems and no issues or problems under boost . Supercharger was installed by Toyota of Cerritos about 5 years ago including a flash tune . Also the 2.7 comes with either blue or pink injectors and I've got the pink injectors , pink I was told are the high flow injectors

A week or so during the last Santa Ana winds I had to drive up the Cajon pass and with 50mph head winds made for a fun time climbing the pass . I was pushing it hard and heard the supercharger whining as I was climbing the grade . No CEL but without an intercooler I was stuffing hot air into my motor the entire 10 mile climb up the pass

Forgot to mention I've only got 54k original miles on my truck if that helps

 

So, Toyota is now saying that they think it's my spark plugs and wires. Even though they have under 30k miles on them, they're the original ones from 2004 and that their poor condition is causing the truck to run lean. At least that's their latest theory, they said on their test drive under heavier throttle they detected spark knock which lead them to this conclusion. Anyway, I gave them the go ahead to change them out, let's see where this goes...

 

Spark plugs probably have their own problem. But the running lean problem is probably either 02 sensors or the Cat Converter.

 

That's what I'm thinking too, I mentioned that to the service advisor and he said their techs already checked them (o2 sensors) and that they were okay, so they're thinking it's due to the plugs. Seems odd that bad plugs would cause the truck to run lean but that's what they say. I did look it up and it's not unheard of, but o2 sensors are a much more likely culprit.

At any rate, this is all pretty frustrating but I knew I'd likely run into a few annoyances buying a 12 year old truck. Makes me happy I chose to go with the ext warranty lol.

 

Sounds like typical dip-shittery at the stealership. I know people who go 150k on stock plugs before a problem pops up.

 

Damn, 150k on the stock copper plugs? The '04 manual says to switch 'em every 30k, I figured they should last longer than that but 150 is nuts lol.

with my supercharger I can only assume the stock plugs I have are probably under a lot more stress than they would've been under normal conditions, and I have no idea how hard the previous owner drove the truck. I've been babying it, especially with this lean code that won't friggin go away.

Slowly narrowing it down to the fact that I'll probably need to drop the coin on the 7th injector kit to see if that's what's doing it, for now I'll use my warranty to let the dealer try and figure it out.

 

Well, in any case, it's free to at least check the plugs, see if they're in good shape or not.

 

Maybe the previous used the wrong plugs....

 

^^^this could be true...the charger does require different plugs than a non charged motor also...

 

So they changed out the plugs and wires, called me back to say that didn't get rid of the P0171 code...surprise surprise. At least now I have a brand new MAF, plugs and wires though

Told me that they were concerned it had to do with the previous dealership doing "a messy job of detailing the engine bay" before selling it to me, wtf?

I casually mentioned that maybe it was an o2 sensor issue again and he was like, "oh...sure, yeah we'll have to look into that".

So NOW they are looking in the o2 sensor, which from everything I've read about this code is the second most common reason for it, after a dirty MAF sensor. These are Toyota's finest? A messy detail job makes the engine run lean, really? The saga continues....

 

Honestly I would take it to another dealership, I wouldn't trust this dealer anymore. Just my two cents.

 

yeah, I agree. Just sucks because I need to leave it there while I'm at work, and it's only a mile from where I work. After I get it back tonight if there are still issues I'm taking to San Diego this weekend to have the dealer I bought it from make the code right.

 

You're the dude that said he had a 2.7 TRD s/c? You wouldn't happen to have a pic of the engine bay would you? I wasn't aware that TRD had offered a 4 cyl s/c.

 

I don't think TRD did, I think URD had the popular s/c kit for the 2.7l.

http://www.urdusa.com/store/Forced-...coma-2.7L-2TR-FE-4-Cylinder/product_info.html