Unsolvable P0171 'System Too Lean' Code

Me either, @DustStorm4x4 you have a special Taco haha

 

Strange. Anyways thank you. Sorry for clogging up the thread full of useless bs.

 

all 01-04 should have the secondary release. I push up on the handle thru the grill.

however @DustStorm4x4 if you just stick your hand between the hood and grill you can "swipe" the lever and get the hood up.

 

Ah, good to know...I wasn't aware of any secondary release.

lol no worries man, we might as well talk about something until I get my truck looked at on Monday for this code, then we can hopefully talk about mods and wheeling after she's all fixed up

 

Update:

So I've been at the Toyota dealer in San Diego (where I bought my truck) all morning. They've had a difficult time with it as well, trying to find the source of my fuel system running lean. The code actually went away yesterday and has stayed off, even on my 150 mile trip to this dealer. But I know better than to expect that my truck magically fixed itself.

The tech here says he thinks he's narrowed it down to an exhaust leak, but he doesn't have the right tool to confirm it. Waiting now to see if it's something they can bring in today or if I need to make another appointment, either way I think we're finally narrowing in on it.

 

When ever i see a lean code, vacuum and exhaust leaks are the first thing I look for always do your visual inspection first before anything else, do you know where the fuel trim is at when it sets a code? I find it hard to believe that their throwing sensors at it and plugs/ wires it must be a new guy thats working on your truck.

 

Seriously, this is beyond frustrating. I had to leave my truck there today, drive all the way back to LA so they can have their 'master tech' work on it tomorrow, then drive all the way back to SD to get my truck after work tomorrow night. Can't wait until this fiasco is over with

 

At least I got a free rental for the next 24 hours, and I had to push for that....

 

Ah gosh what a fiasco! This is gettin old and im not even affected by it, lol! I can only imagine how youre feeling. Whats really gunna be lame is when tomorrow they call you and tell ya they cant find or figure it out...

 

Dude tell me about it lol. Oh man, if that happens tomorrow I'm going to flip...there's no way it's this hard to fix a flippin' lean fuel system. In their defense though, the service advisor sat me down this afternoon and showed me a step by step list of everything they've checked to try and pinpoint it today, and everything on their list were the things (and then some) that I've read to check on here and elsewhere. It's a mystery alright.

I'm starting to wonder if maybe the previous owner never got the ECU reflashed for the supercharger, and if that would make this code pop up? After all, a lean fuel system code is thrown when the ECU detects too much air entering the system than it's programmed for, right? And a supercharger definitely puts more air into the motor than the stock ECU is programmed for...I dunno, I'm starting to think a bit outside the realm of standard possibilities now...but if that were the case then the code would have definitely come up right after I got the truck, not 3 weeks after having it.

 

I was reading through some first gen/supercharger threads just now, forgetting about my truck's dilemma, and I got all excited for a sec and decided I'd go take my truck out for a little joyride....


...then I remembered I left it at Toyota 120 miles away and I have a rental Prius

 

Ahh haha lame, definitely not gunna "joy ride" the prius...

So im not all savy on ecu stuff but for some reason i dont think our ecu's can be flashed...someone else will know this for sure....i also dont think the trucks with chargers have a different ecu either, i thought they were all the same. But again this isnt my forte so to speak! Have you read other wise in your readings lately??

@Dirty Pool how bout it? What do you know about this stuff?

 

Sorry not reflashed, but programmed to the supercharger's specs...at least I thought I remembered reading on here that the ECU needed to be updated after the s/c install. Maybe I'm just going crazy from all of this, that's also entirely possible.

 

Ive had that exact same thing happen to me i was renting a pruis and forgot and the thought crossed my mind hey lets go wheeling i even went outside and i was like shit i have a pruis

 

Never say never https://www.tacomaworld.com/threads/2007-toyota-prius-off-road-build-all-toyotas-can-crawl.424427/

 

Yes ive been following that haha if i had the space and time id finish that thing, but to many projects around the house and a camper that needs some major tlc

 

UPDATE:

According to the Master Service Tech, he found a port on the back of my TRD supercharger that was partially uncapped and creating a small vacuum leak that was setting of the code....

WHY DID IT TAKE TWO DEALERSHIPS 5 DAYS AND A MASTER TECH NEEDING TO BE CALLED IN TO DIAGNOSE A VACUUM LEAK!

Oh and they also informed me that my fuel filter needs to be changed 'soon'.

Needless to say, I'm not entirely convinced and I feel like they are just trying to get me on my way because my 30 day bumper to bumper warranty is about to expire (actually, it expired yesterday). They said they cleared the code and it has stayed off, so maybe that was it...who knows, I guess time will tell.

Now that I think about it, there were times when I'd hit the gas and it really felt like the supercharger wasn't performing as well as it should. I dunno, it just felt inconsistent at times. So maybe they did find an issue there. When I pick it up tonight I'll report back...god help me if that code comes back on when I'm driving home...

 

It's conceivable that that could be your trouble.

Hope that's it.

 

Just got home after the 120 mile trip back, all is well so far. But they did disconnect my battery at one point and I know from experience that it can take several hours of driving after that for the ECU to pick up the code again, so my skepticism isn't gone completely but so far, so good.

Also, there is a noticeable increase in throttle response especially when I wake up the supercharger, so I'll take that as a good sign, and my MPG is back to normal...20.3 MPG on my trip back home which is great considering I was boosting quite a bit on the freeway. Hope all is well, I'll report back in a few days

Thanks for all your responses!