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P0171 system too lean bank 1

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delhusband
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P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 8:05 am

Hi, had my lhs O2 sensor out and back in yesterday. Don't know if it's related, but got eml. Checked fault code with my Bluetooth reader, it's saying p0171 power train, system too lean bank one, can anyone advise?
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
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Justin.D
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Re: P0171 system too lean bank 1

Postby Justin.D » Tue Aug 01, 2017 10:22 am

I had this but with P0174 Bank 2. First thing is to determine if it's a duff sensor - I would swap the sensors over and see if the problem stays at bank 1 or follows the sensor

My issue followed the sensor so I got a new one and fitted it myself - All fixed. Hopefully yours will be an easy fix

m1tch
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Re: P0171 system too lean bank 1

Postby m1tch » Tue Aug 01, 2017 11:20 am

Are you seeing voltage on all 3 sensors?

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 11:30 am

I'll try and check, bit new to using odb2 reader but I reckon I know how to add dials to check this. I'll have a look this lunchtime and report back
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 11:54 am

Yeah, Ok, 0v sensor 1. I'll check it's not loose termination of plugs/melted cable. Guess OtherStu right enough about playing with these! Image
Image
'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
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Mrcypher
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Re: P0171 system too lean bank 1

Postby Mrcypher » Tue Aug 01, 2017 2:52 pm

I had this other day, unplugged and replugged all sensors and made sure was connected proper, seems to have stayed off for now but i get a different code every other journey with the full decat...

It can also relate to maf aswell so might be worth giving that a clean, also check no leaks from induction/air box

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Re: P0171 system too lean bank 1

Postby m1tch » Tue Aug 01, 2017 4:01 pm

Looks like your right O2 sensor on the manifold might have failed - is the engine up to temp etc?

Also what are your long term and short term fuel trims?

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 5:36 pm

During short drive, car warm
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 5:38 pm

Idling, car warm
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Image
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 5:42 pm

OK, rhs O2 plug loose, reconnected, I'll try again, sorry
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 5:47 pm

With rhs plugged in properly, during drive
Image
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 5:52 pm

So, I think that means O2 sensors are OK, just didn't plug rhs one back in properly. I removed both plugs, but only physically removed lhs sensor from manifold. Does that sound right?
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 6:01 pm

Thanks M1tch, Justin & Mr cypher. I've been a tw@t. Because I'd only physically removed the lhs I wasn't paying attention to rhs. Note to self, check twice before posting. Thanks again, pants of shame application in the post
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

Chilli Girl
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Re: P0171 system too lean bank 1

Postby Chilli Girl » Tue Aug 01, 2017 7:24 pm

We've all been there Derek. Foxy's side windows kept misting up, thought there was a problem with the demister, couldn't work out the problem at all, it was because I had the side vents shut all the way along! I felt a right idiot.

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Tue Aug 01, 2017 9:04 pm

Chilli Girl wrote:We've all been there Derek

Lol! I'm there on a daily basis Jane
Mind you, the guy I bought the car off thought his passenger window was broken, until i showed him the override switch :)
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

paulj
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Re: P0171 system too lean bank 1

Postby paulj » Thu Aug 03, 2017 5:52 pm

I hope you didn't show him until after you agreed a price
Today
2000 x reg pfl - blue - as original no mods
In the late 1980's
1982 x reg Toyota Corolla Liftback Coupe (also blue)
1978 s reg Mitsubishi Celeste Coupe (yellow)

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Thu Aug 03, 2017 9:52 pm

paulj wrote:I hope you didn't show him until after you agreed a price

*sigh* no, I'm a sucker, I almost gave him full asking price. I got all misty eyed and excited at the
prospect of having another 2. He did very kindly provide a set of discs and pads to cover the mot advisory on the car
Image
'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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KTM_RIDER
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Re: P0171 system too lean bank 1

Postby KTM_RIDER » Fri Aug 11, 2017 8:23 am

delhusband wrote:With rhs plugged in properly, during drive
Image
Image


that all looks very handy - I think things have moved on in the last few years - is this the torque app ? Does it just require a random generic ebay bluetooth obd port adaptor to work?
Alan

2003 Blue FL / 2003 Red FL / 2000 Blue PFL
Fabia 1.4TDI PD / KTM 390 Duke / KTM 640 Duke 2

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Fri Aug 11, 2017 2:15 pm

Hi, yeah this was torque app on android smartphone, with an elm327 Bluetooth dongle
See here for pic (maybe... I'm still trying to get used to Flickr!)
https://flic.kr/p/XxaEpr
Image
'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Fri Aug 11, 2017 2:22 pm

I won't pretend I understand these graphs. I was really just looking for non zero values on O2 sensors. I'm learning though.... :)
Image
'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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Re: P0171 system too lean bank 1

Postby shnazzle » Fri Aug 11, 2017 3:42 pm

Don't. Fuel trims leads to timing, timing leads to engine management, that is a rabbit hole and I can't find the way out

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Fri Aug 11, 2017 4:14 pm

Lol! E2V has kindly given me some reading to do - Currently in the Haynes guide to tuning. For now, MAF and intake temp graphs self explanatory, fuel trims I guess is fuel feed adjustment based on many inputs so i guess i would need to look at more data to understand better.
Its the O2 graphs that got me mesmerised. I O2 voltage on 1x1 dip and O2 2x1 spike coincided with acceleration/increased throttle. I take it voltage decreases with reducing O2?
I'd have guessed, if +v = + O2, then on the graphs above, O2 1x1 is exhaust, O2 2x1 is intake, and i have no idea what O2 1 x 2 is telling me because i thought that was also intake on other side of heat sheild from 2 x 1. I dont understand.
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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Re: P0171 system too lean bank 1

Postby delhusband » Fri Aug 11, 2017 4:35 pm

Yeah, and timing! who knew there was a position sensor on the crankshaft that helps change ignition timing based on rotation speed to make sure expansion happens at the right rate and time! (Probably a lot of peeps on this forum except me :D ). Back to my books......ive only had idiots guide to 4 stroke before now, much more to learn
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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Re: P0171 system too lean bank 1

Postby KTM_RIDER » Fri Aug 11, 2017 9:51 pm

delhusband wrote:Hi, yeah this was torque app on android smartphone, with an elm327 Bluetooth dongle
See here for pic (maybe... I'm still trying to get used to Flickr!)
https://flic.kr/p/XxaEpr


Thanks

delhusband wrote:Yeah, and timing! who knew there was a position sensor on the crankshaft that helps change ignition timing based on rotation speed to make sure expansion happens at the right rate and time! (Probably a lot of peeps on this forum except me :D ).


Well I might have got there eventually...... (I can vaguely recall the existence of the ignition advance / retard concept and I was aware of crank p.s. just hadn't stopped to consider what the ECU would be doing with the information :) ).

Have always been more interested in the nuts and bolts side of engines which haven't fundamentally changed from the first one I worked on 31 years ago (a points ignition, 100cc air cooled single Suzuki motorcycle engine).
Alan

2003 Blue FL / 2003 Red FL / 2000 Blue PFL
Fabia 1.4TDI PD / KTM 390 Duke / KTM 640 Duke 2

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Fri Aug 11, 2017 10:21 pm

KTM_RIDER wrote:Well I might have got there eventually...... (I can vaguely recall the existence of the ignition advance / retard concept and I was aware of crank p.s. just hadn't stopped to consider what the ECU would be doing with the information :) ).

Have always been more interested in the nuts and bolts side of engines which haven't fundamentally changed from the first one I worked on 31 years ago (a points ignition, 100cc air cooled single Suzuki motorcycle engine).

Hi KTM_RIDER, that comment i made about timing, that was in response to shnazzles quote, hope i didnt come across as really rude, because i literally am clueless about engine management. I'm trying to understand what i was seeing on torque. :bowdown:
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'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536

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shnazzle
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Re: P0171 system too lean bank 1

Postby shnazzle » Fri Aug 11, 2017 11:03 pm

I'm clueless about it and I've been reading up and tinkering for over a year

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KTM_RIDER
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Re: P0171 system too lean bank 1

Postby KTM_RIDER » Sat Aug 12, 2017 7:20 am

Did I find you rude? - no, not even remotely (forums are great for alot of things including generating misunderstandings :lol: )

Perhaps in a rather convoluted fashion I was trying to respond to this comment............

delhusband wrote:who knew there was a position sensor on the crankshaft that helps change ignition timing based on rotation speed to make sure expansion happens at the right rate and time! (Probably a lot of peeps on this forum except me :D ).


............with a response that indicated I had a less (EDIT - ok very much less ) than firm grasp of this stuff myself despite (but also to some extent because of) working on my own vehicles for the last 31 years

I say to "some extent because" as the (motorcycle) engines I was pulling apart in the late 80s didn't have engine management - they didn't even have fuel injection. Whereas if I was starting out as a DIY mechanic today then I suppose i would be alot more keen to read up on E.M.

Engine management (as the term is generally understood today anyway) came along with EFI and Catalytic converters. When I started owning the odd car in the 90s I purposely avoided anything with a Cat on the basis that this was one less thing to go expensively wrong :)

Apart from a motorcycle I briefly owned around 2005, the first Cat and EFI equipped petrol engined vehicle I owned was my first MR2 Roadster in 2010..........

The other thing about E.M. is that (in my experience) it tends to just work, so I've had no reason (so far) to learn about it, although I wouldn't mind squeezing a bit more power out of my Roadie at some point.......

This quote makes me feel better :)

Modern engine management systems do a fine job of ensuring that engines run cleanly and efficiently in a wide variety of conditions, they are for the most part reliable and require little or no maintenance. However they seem from the outside to be fearsomely complicated systems which defy all attempts at understanding. Amidst all this apparent hokum it is easy to lose sight of the two basic functions performed by an EMS.

To meter fuel to the engine in the right quantity

To provide a spark at the right time


Taken from:

http://www.s262612653.websitehome.co.uk/ems/
Alan

2003 Blue FL / 2003 Red FL / 2000 Blue PFL
Fabia 1.4TDI PD / KTM 390 Duke / KTM 640 Duke 2

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Re: P0171 system too lean bank 1

Postby KTM_RIDER » Sat Aug 12, 2017 7:57 am

I recall that when I was on here between 2010 - 2012 there was no -one who seemed to understand E.M. on our cars better than Cap:

memberlist.php?mode=viewprofile&u=9566

So you might want to check out some of his posts - just a thought.
Alan

2003 Blue FL / 2003 Red FL / 2000 Blue PFL
Fabia 1.4TDI PD / KTM 390 Duke / KTM 640 Duke 2

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delhusband
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Re: P0171 system too lean bank 1

Postby delhusband » Sat Aug 12, 2017 5:57 pm

Thanks! Relieved no offence caused, sometimes when i reread what I've typed i cringe a bit :) also thanks for this
KTM_RIDER wrote:I recall that when I was on here between 2010 - 2012 there was no -one who seemed to understand E.M. on our cars better than Cap:

memberlist.php?mode=viewprofile&u=9566

So you might want to check out some of his posts - just a thought.

Ill have a look
Image
'06 Silver FL - Vanilla, skinny half sugar. (modless stock 1ZZ, -precats, +blitz lm panel filter)
Readers ride:http://mr2roc.org/phpBB3/viewtopic.php?f=88&t=62450&sid=069c764a710cd192b0aa8bac145c2536


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