P0140 code help understanding
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Pro
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From: San Antonio Texas
P0140 code help understanding
Hi folks. Need some help with a code. I got a CEL and pulled code. It is the P0140. I looked up the code on the list but I am not sure I know what it means. My understanding at this point is that my rear left O2 sensor is bad but I can't seem to be able to confirm that. Anyone know for sure if I am correct? I purchased p/n 13111 and am ready to replace but just thought I would ask for confirmation. Many thanks in advance for any help.
Paul
Paul
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From: Atlanta GA
Hi folks. Need some help with a code. I got a CEL and pulled code. It is the P0140. I looked up the code on the list but I am not sure I know what it means. My understanding at this point is that my rear left O2 sensor is bad but I can't seem to be able to confirm that. Anyone know for sure if I am correct? I purchased p/n 13111 and am ready to replace but just thought I would ask for confirmation. Many thanks in advance for any help.
Paul
Paul
This code states that the sensor is not communicating, which means the CAN ECU is not receiving any info from the sensor as expected. Any other codes being thrown in addition to this code?
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Thread Starter
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Joined: Aug 2010
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From: San Antonio Texas
[QUOTE=8VETTE7;1595895830]Could be a bad sensor or it could be damaged wiring to the sensor or even a damaged connector.
Code just points you in the direction of the problem. YOU need to examine the environment before just changing parts. JMHO[/QUOTE
As I suspected it was the rear left sensor. After 50,718 miles and twenty years it gave up. I replaced the sensor and reset the code. All is well at this point. And thank you for the advice regarding examining the parts before just replacing them. My question was about confirming I had the correct sensor indicated by the P0140 code as it just says which bank and which location. It never hurts to ask. But thanks for the tip.
After 50 years of working on cars, boats and aircraft I know I can always learn something.
Code just points you in the direction of the problem. YOU need to examine the environment before just changing parts. JMHO[/QUOTE
As I suspected it was the rear left sensor. After 50,718 miles and twenty years it gave up. I replaced the sensor and reset the code. All is well at this point. And thank you for the advice regarding examining the parts before just replacing them. My question was about confirming I had the correct sensor indicated by the P0140 code as it just says which bank and which location. It never hurts to ask. But thanks for the tip.
After 50 years of working on cars, boats and aircraft I know I can always learn something.
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Joined: Aug 2010
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From: San Antonio Texas
You are right that the code is related to a O2 Sensor circuit. However, the 02 sensor could be bad or it could be a lose connection or related to something else.
This code states that the sensor is not communicating, which means the CAN ECU is not receiving any info from the sensor as expected. Any other codes being thrown in addition to this code?
This code states that the sensor is not communicating, which means the CAN ECU is not receiving any info from the sensor as expected. Any other codes being thrown in addition to this code?
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Agree with all above But I would also check your Driver's side front 02 voltages---The sensor may just be bad along with the other intake issue
To properly check a front 02 you'll need a good scanner or tuning device such as HP Tuners or EFILIVE
The front 02's when the engine is running "oscsilates" or changes rapidly from .100 to .950 Millivolts
Make sure it is doing that----------Then there is also an "Average 02 voltage" this is very important --The average should be between .400 and .550 Millivolts--- A dead 02 normally will Flatline on .450 with no oscilation---
Remeber that the front 02's command and run your fueling at P/T all the time using the voltages to add or subtract fuel based on their readings Using the fuel triims to correct the fueling to the STOICH of 14.68-1 ----
To properly check a front 02 you'll need a good scanner or tuning device such as HP Tuners or EFILIVE
The front 02's when the engine is running "oscsilates" or changes rapidly from .100 to .950 Millivolts
Make sure it is doing that----------Then there is also an "Average 02 voltage" this is very important --The average should be between .400 and .550 Millivolts--- A dead 02 normally will Flatline on .450 with no oscilation---
Remeber that the front 02's command and run your fueling at P/T all the time using the voltages to add or subtract fuel based on their readings Using the fuel triims to correct the fueling to the STOICH of 14.68-1 ----
