Motor Vehicle Maintenance & Repair Stack Exchange
Motor Vehicle Maintenance & Repair Stack Exchange

Questions tagged [p0171]

Code P0171 - System Too Lean. This code indicates an oxygen sensor has detected too much oxygen in the exhaust. Part of the P01xx - Fuel and Air Metering family of codes.

On-board Diagnostics Wikipage

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Are widebands known to go lazy over time?

I know narrowbands can go lazy with time, but what about widebands? This is a sequel to the cold-start misfire mystery. It turns out that we were looking at the wrong PID's for the front O2 sensor voltages, assuming they were narrowbands. Probing…
Zaid
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P0171 and Fuel Trims

I have a 2002 Toyota Corolla (1zz-fe engine) and I am getting a P0171 code - lean condition. I am trying to make sense of my fuel trim values and I was hoping someone could help understand these results: I am measuring on Neutral, after the engine…
Florent
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'Check Engine' code P0171 System Too Lean - Is it safe to drive?

My 2003 Toyota Corolla's Check Engine Light came on. I read the codes using an OBD code reader and got P0171 - System Too Lean (Bank 1) and P0133 - 02 Circuit Slow Response (Bank 1, Sensor 1). The light is on solid, not blinking. From what I can…
culix
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Fuel Trim Readings

I have a 2002 Toyota Corolla (1ZZ-FE engine) and I am trying to understand the fuel trim values I am getting in real driving conditions from my scan tool. I have P0171 code (lean condition) that comes on and off. I posted earlier about this, but I…
Florent
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Diagnosing P0171 2007 Toyota Corolla

First time poster trying to get into cars. So my 2007 Toyota Corolla (with around 89k miles) has a Check engine light that reads error code P0171 (System too lean Bank 1). I was looking that up and the few causes are: Intake/Vacuum…
FettFrank
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P0171: what to look at next, after MAF, O2 senors, fuel filter, and vacuum?

I have been chasing a P0171 on a project vehicle for quite some time now. This is a 1999 4Runner with the 5VZ V6 engine, 70K miles, naturally aspirated. For this particular model-year there was no EGR. So far everything I've looked at has been…
Cognitive Hazard
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Help with P0171 code

I've been struggling with a p0171 code since I've bought my car (second hand). It's a Honda hrv 2016. I've already taken to Honda service several times. They made me change the lambda sensor, maf sensor, fuel filter and still no luck. On long drives…
Guz
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Vehicle not storing freeze frame data when it sets OBD P0171 code

I have an 05 Hyundai Tucson with 2.7L engine with 85,000 miles. It is setting a P0171 lean bank one code. However, both banks are operating at near the high threshold levels around 14.8%. Numerous attempts and test have been tried to resolve the…
Ronnie3945
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PO171 trouble code at idle

My Toyota Vitz (Yaris) 2007 randomly gives PO171 (System Too Lean) when at idle. My mechanic has done following fixes so far, but problem still persists. Replaced oxygen sensors. Replaced fuel filter. Cleaned injectors, spark plugs. Also, mechanic…
Softcode
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Corolla gives me a P0170 code

I had an issue when sometimes my 2000 1.8L Corolla stalls if I roll in reverse. A few weeks later, I got a check engine code pointing to Bank 1 Sensor 1 as an issue. I replaced it, cleared the codes and thought it was cured. A few weeks later, the…
ATL_DEV
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Error MIL: off Spark ignition

I checked my OBD2 sensor and it shows on DTC that message. Along with P0171 system too lean on my Mazda 3. I put in an injen intake and that was 3 years ago. The check engine light came on 3 months after installing the new cold air intake. Any idea…
user12041
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Mazda 323 / Protege 2001 power problem

Here is my name, Fabien My friend bought a 323F 2001 with 58 000 km, it's the 1.6 DOHC engine with 98 HP ( 72 KW ). We live in France We got a problem to make the car running great. For now, the car start and idle correctly cold and hot... The…
LegeekX3
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P0171 and P0174 in 2008 Range Rover HSE

I have a 2008 Range Rover HSE with 147,000 miles. I got a check engine light and the PID indicated catalytic converters in bank 2 were bad. I replaced the cats and then started getting P0171 and P0174 messages. I replaced the air filter and the…
MickeyD2556
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02 upstream wire harness diagram

I have a 1996 Dodge Neon 2.0 L Vin C. DTC P0171 when I went to change 02 Sensor. I saw that my upstream 02 sensor connector harness side got melted, was to close the the exhaust. Don't know how to find which wire goes where, how do I figure this…
William9
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Codes like P0171, P0101

My 2001 Nissan Sentra shows a P0171 and P0101 code. I tried to clean the sensor and the part after that (I don't know the name) and it's still showing the engine light. The sensor seems like new to me and I want to know if I really have to change…
Penelope Castin
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