P0171 System Too Lean fixed on 2010 Prius

What code did you get?

 

Hi there. Im currently use gen3. My car having the same fault code . I have done quite extensive job like lexibothersome for the troubleshooting. Finally, toyota advice my local mechanic to chg the fuel pump. I went up calling few parts supplier and eventually found complete assy new set for 700usd. Expensive fix but no fault code anymore.

Posted via the PriusChat mobile app.

 

I have the same error code, too.
Thank you so much to share your experience.

Could you please share with me also the pdf manual link?

 

See this page 1 posting:

P0171 System Too Lean fixed on 2010 Prius | PriusChat

 

I also had the Gen 3 Prius Repair Manual on PDF. Pages 3015 thru 3025 cover the fuel pump installation.
If anyone would like the PDF, please send me a message and I'll provide you with a Google Drive link.[/QUOTE]


I'm getting the same thing. I've got 147K on a 2010 Prius 2. It says "P0171 Intake system, Injector Blockage ,Mass Air slow meter,System too lean Bank 1. I did replace the EGR valve because I knew it needed it but that didn't fix it. I have had the car since 25K miles (If I remember right which is unlikely.) I used to average 44 mpg but now I'm around 40. Can you send me the google drive link?

 

Had trouble with my 2011 Gen 3 with 70,000 miles the other day. It started rough and stalled after a few seconds repeatedly. There seemed to be a noise from the engine bay. There was a check hybrid system warning and a warning (can’t remember acronym) about pre collision assist ( I have a version with adaptive cruise control) It showed a P3190 code.

I’m in Australia. It was very cold for here (below 50 F, 9 C ) the previous night and it seems my 5 year old 12v battery would have been under 12v. Later that day I managed to keep the engine running after clearing the P3190 code. The traction battery was down to one bar. I took it for a 50 mile country drive afterwards. It ran fine but threw a P0170 code after stopping half way which I cleared straight away.

I have since done another 70 miles. The P0170 code comes up about 10 minutes after restarting the engine each time. I clear it and it doesn’t come up again til the engine has been restarted.

Pardon this confusing post. I cannot afford a mechanic or to replace the 12v battery at the moment. I’m keeping the 12v battery on charge to see if that makes a difference.

I suspect it’s fuel filter/pump even though it was changed as part of a recall 20,000 miles ago. I understand we have a different fuel system to the US.

Any ideas?

 

I'd get a code reader to determine the codes.

Best cost effective code reader is to look for the mini VCI reader and pair it with an old Windows Laptop.

That's what I have and it works well for determining the actual root cause of the issue and resolves the potentials.

 

Thanks Ray. I do have a generic ELM327 wifi reader that I use with my iPhone, but I’ve ordered a Dr Prius compatible one with Bluetooth so I can use the DP app. I couldn’t source a mini VCI cable and my laptop is a 64bit Macintosh. Windows 7 laptops are surprisingly hard to find. At least I’ll be able check the condition of the traction battery.

As it turns out, the P0171 error was attributable to my idiocy. The large 3”+ hose from the air filter was loose. I’d dislodged it checking the air filter just before the initial P3190 code. The Toyota service guys seem to leave the clamps really loose. Just took it for a 10 mile drive and the check engine light and P0171 code didn’t appear.

 

If you're able to source a mini-vci cable, you might try emulating a windows environment (XP or better) by using :

• https://www.winehq.org/
• Oracle VM VirtualBox
• Base camp?
• Favorite emulator

 

Thanks for your thread OP. I just got the code on my 2014 with 243k mi. Would you mind sending google drive link to Gen 3 pdf repair manual?

 

See post #9; think that’s what you want.

 

That’s it. Thank you

 

I'm trying to work through the steps to diagnose a P0171 and having some trouble interpreting the confirmation driving pattern. This is cobbled together from pages 2341-2342 of the repair manual:

In #6 you put it in inspection mode so the ICE doesn't turn off for #7 (warming the engine) and #8 (idling). But #9 wants you to drive the vehicle, without leaving inspection mode. I always thought one wasn't supposed to drive in inspection mode. What am I missing here?

 

Does the [C] at the end of step #8 link to anything helpful?

I'd guess turn it off and restart (bail from maintenance mode).

 

Good question. It's kind of like "no user-serviceable parts inside".

You're not supposed to drive in inspection mode when there isn't a very good reason (such as a Repair Manual procedure, for a code that you have, telling you to do it). And if you're going to do it, you're supposed to understand the mechanical reasons and risks that are behind the normal warning not to do it, and drive with great care to avoid those conditions.

That's a little easier in Gen 3, which separated out the "inspection mode - 2WD for measuring exhaust gas" from the "inspection mode - 2WD for cutting TRC" into two separate modes. Or at least if the first mode doesn't still cut TRC also, which the repair manual seems in one spot to say it does. Go figure.

 

I think only the INFO buttons link to other sections. The [C] at the end of step 8 is just referring us to [C] in the chart (idling).

That's what I tried a couple of times yesterday, but steps 15 and 17 both returned INCOMPLETE.

This makes sense to me. I have found the manual to be pretty descriptive, and I found it a little unlikely that they would skip such an important step. For instance, the confirmation pattern it describes for P060B (which I don't have, and which is unrelated to P0171) has explicit instructions for switching between IG and READY modes.

 

My mileage dropped when my tires were changed…. Wrong kind for a hybrid. When I got the right tires I could feel the difference - they pulled my car soon as I took my foot off the break. Not saying this is your issue or anyone else’s. Just for those new to the hybrids verify you get the right kind of tires when replacing. 5 MPG adds up…

when I tried this last time to get Hybrid tires for my 2007 Prius the newer cars are a different size: it was hard to find them to fit older models anymore.

 

can I asked for the repair manual. Appreciate you my friend.