Code P0171, P0174
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
Code P0171, P0174
Hey guys just got my 2011 ZR1 ,on the road today to go and get a front end alignment. Drove about 45 miles stop and go then before reaching home got the check engine light popped on hooked my scanner up and got these codes. Po171 and 174 left and right bank lean.
Looked in my service manual and one item says possible cause incorrect air filter,
I had removed stock filter and put in a K&N air filter anyone had a similar problem with K&N ? I have not changed it yet thought I would check with the experts first.
Looked in my service manual and one item says possible cause incorrect air filter,
I had removed stock filter and put in a K&N air filter anyone had a similar problem with K&N ? I have not changed it yet thought I would check with the experts first.
Drifting
Joined: May 2010
Posts: 1,273
Likes: 74
From: Fairfield County, CT
To keep the engine running properly, the Engine Control Module measures the oxygen content in the exhaust with oxygen sensors and makes adjustments to the mixture by injecting more or less fuel. The control module operates within specific parameters and under normal conditions, it will make minor adjustments to the air/fuel mixture. When these adjustments become too large, a fault code is set. When the P0171/P0174 code sets, the oxygen sensors are detecting too little oxygen in the exhaust and the control module is adding more fuel than normal to sustain the proper air/fuel mixture.
Common Problems That Trigger the P0171 and P0174 Code
PCM software needs to be updated
Vacuum leaks (Intake Manifold Gaskets, vacuum hoses, PCV hoses, etc.)
Mass Airflow Sensor (MAF)
Plugged Fuel Filter or weak Fuel Pump
Plugged or dirty Fuel Injectors
In your case, you may need the car tuned to accommodate ant changes in air flow from the new filter.
Check out http://www.obd-codes.com for more info.
Good luck.
Common Problems That Trigger the P0171 and P0174 Code
PCM software needs to be updated
Vacuum leaks (Intake Manifold Gaskets, vacuum hoses, PCV hoses, etc.)
Mass Airflow Sensor (MAF)
Plugged Fuel Filter or weak Fuel Pump
Plugged or dirty Fuel Injectors
In your case, you may need the car tuned to accommodate ant changes in air flow from the new filter.
Check out http://www.obd-codes.com for more info.
Good luck.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
To keep the engine running properly, the Engine Control Module measures the oxygen content in the exhaust with oxygen sensors and makes adjustments to the mixture by injecting more or less fuel. The control module operates within specific parameters and under normal conditions, it will make minor adjustments to the air/fuel mixture. When these adjustments become too large, a fault code is set. When the P0171/P0174 code sets, the oxygen sensors are detecting too little oxygen in the exhaust and the control module is adding more fuel than normal to sustain the proper air/fuel mixture.
Common Problems That Trigger the P0171 and P0174 Code
PCM software needs to be updated
Vacuum leaks (Intake Manifold Gaskets, vacuum hoses, PCV hoses, etc.)
Mass Airflow Sensor (MAF)
Plugged Fuel Filter or weak Fuel Pump
Plugged or dirty Fuel Injectors
In your case, you may need the car tuned to accommodate ant changes in air flow from the new filter.
Check out http://www.obd-codes.com for more info.
Good luck.
Common Problems That Trigger the P0171 and P0174 Code
PCM software needs to be updated
Vacuum leaks (Intake Manifold Gaskets, vacuum hoses, PCV hoses, etc.)
Mass Airflow Sensor (MAF)
Plugged Fuel Filter or weak Fuel Pump
Plugged or dirty Fuel Injectors
In your case, you may need the car tuned to accommodate ant changes in air flow from the new filter.
Check out http://www.obd-codes.com for more info.
Good luck.
Only has 11,000 miles, no vacuum leaks I can detect.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 262
From: St. Louis, MO
St. Jude Donor '08
That's a vacuum leak code most of the time. Retrace your steps installing the air filter...did you remove the air cleaner? Perhaps not get it fully reinstalled? Knocking a vacuum line off normally won't be enough of a leak to set the code, the code comes up when the car needs more than 25% of fuel added to maintain stoiometric.
Sometimes folks will get their air filters too oiled and the oil fouls the maf sensor. Any chance this happened? You should probably pull the maf and clean it with maf cleaner but be careful it's a sensitive device with thin wires down in there.
Sometimes folks will get their air filters too oiled and the oil fouls the maf sensor. Any chance this happened? You should probably pull the maf and clean it with maf cleaner but be careful it's a sensitive device with thin wires down in there.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
That's a vacuum leak code most of the time. Retrace your steps installing the air filter...did you remove the air cleaner? Perhaps not get it fully reinstalled? Knocking a vacuum line off normally won't be enough of a leak to set the code, the code comes up when the car needs more than 25% of fuel added to maintain stoiometric.
Sometimes folks will get their air filters too oiled and the oil fouls the maf sensor. Any chance this happened? You should probably pull the maf and clean it with maf cleaner but be careful it's a sensitive device with thin wires down in there.
Sometimes folks will get their air filters too oiled and the oil fouls the maf sensor. Any chance this happened? You should probably pull the maf and clean it with maf cleaner but be careful it's a sensitive device with thin wires down in there.
i did not oil the K&N filter because instructions said it came pre-oiled.
I also looked for any loose vacuum lines but found none.
I cleared the code and will drive it tomorrow and if the code pops up again I will clean the MAF sensor.
I don't suppose having the dual muffler mode fuse removed so it's in the wild position would cause this?
It just seemed to me a lean code on both banks could possibly be the K&N filter since they are designed to flow more air thus causing a lean effect?
anyway I will let you know if the code appears again.
Thanks for you assistance.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 262
From: St. Louis, MO
St. Jude Donor '08
When I'm trying to solve a problem I ask if it worked fine yesterday and doesn't work fine today, what changed between yesterday and today. Usually that points out the cause of problem.
In this case, the only thing I know of that changed is the K&N... so we're focusing efforts there. You've eliminated a bunch of potential problems.
Your fuse being pulled won't cause this. It may cause partial deafness or tinnitus, but you didn't ask about that. lol (I can't stand the sound of NPP at part throttle, the drone is deafening to me).
I think your plan is good and is exactly what I would do. Please remember to update us.
I'm going to guess that the K&N had a little extra oil on it and it got on your maf, and a maf cleaning will take care of it.
If you're able, scan your car and report back what the LTFT's while idling are.
In this case, the only thing I know of that changed is the K&N... so we're focusing efforts there. You've eliminated a bunch of potential problems.
Your fuse being pulled won't cause this. It may cause partial deafness or tinnitus, but you didn't ask about that. lol (I can't stand the sound of NPP at part throttle, the drone is deafening to me).
I think your plan is good and is exactly what I would do. Please remember to update us.
I'm going to guess that the K&N had a little extra oil on it and it got on your maf, and a maf cleaning will take care of it.
If you're able, scan your car and report back what the LTFT's while idling are.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
When I'm trying to solve a problem I ask if it worked fine yesterday and doesn't work fine today, what changed between yesterday and today. Usually that points out the cause of problem.
In this case, the only thing I know of that changed is the K&N... so we're focusing efforts there. You've eliminated a bunch of potential problems.
Your fuse being pulled won't cause this. It may cause partial deafness or tinnitus, but you didn't ask about that. lol (I can't stand the sound of NPP at part throttle, the drone is deafening to me).
I think your plan is good and is exactly what I would do. Please remember to update us.
I'm going to guess that the K&N had a little extra oil on it and it got on your maf, and a maf cleaning will take care of it.
If you're able, scan your car and report back what the LTFT's while idling are.
In this case, the only thing I know of that changed is the K&N... so we're focusing efforts there. You've eliminated a bunch of potential problems.
Your fuse being pulled won't cause this. It may cause partial deafness or tinnitus, but you didn't ask about that. lol (I can't stand the sound of NPP at part throttle, the drone is deafening to me).
I think your plan is good and is exactly what I would do. Please remember to update us.
I'm going to guess that the K&N had a little extra oil on it and it got on your maf, and a maf cleaning will take care of it.
If you're able, scan your car and report back what the LTFT's while idling are.
I rechecked all the plumbing, removed the air cleaner again and checked it.
I don't see any signs of excess oil on the filter in fact I did not even see any oil, so I cleaned the MAF sensor with some Electronics spray. I will try again, but if the code pops again, I will pull the K&N filter and put the stock one back in.
I also checked the fuel pressure with car off ignition on it went right up to about 60 lbs. then very slowly started dropping.
Thanks again
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Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
Did that then was able to drive about twice the distance and number of off's and on's then the codes popped up again.
Just for everyones info the LS9 has very few vacuum lines.
I sprayed some starting fluid on all the vacuum connections figuring if there was a leak the engine idle would change, if there was a leak. Nothing.
I will try a run again soon after disconnectiing the negative cable again.
Thanks
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
By the way I'm going to buy another MAF sensor , have you remove yours before? I know it's simple 2 screws but it's got those bloody Torque screws with the tit in the center.
Went to Harbor Freight bought a Torques socket set that has the hole in the center for the tit but friggin tit was too big and it would.t fit ! My second torques set. Again this is my daily auto repair routine !
Thanks for the info
Burning Brakes
Joined: Dec 2014
Posts: 959
Likes: 24
From: Los Angeles, CA
Link to a set that works for our cars?
To the OP,
I had the same issue with my airaid intake. Installed and then got the same codes only during stop and go traffic. Reset the code and came back one more time. Check the fuel trims to ensure I was good. Reset codes and it has never come back for over 5k miles.
Reset your codes and run it. Everything you reflash the ECM the codes might come back. Mine has come back every time I retune the car but I goes away after clearing them.
To the OP,
I had the same issue with my airaid intake. Installed and then got the same codes only during stop and go traffic. Reset the code and came back one more time. Check the fuel trims to ensure I was good. Reset codes and it has never come back for over 5k miles.
Reset your codes and run it. Everything you reflash the ECM the codes might come back. Mine has come back every time I retune the car but I goes away after clearing them.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
Link to a set that works for our cars?
To the OP,
I had the same issue with my airaid intake. Installed and then got the same codes only during stop and go traffic. Reset the code and came back one more time. Check the fuel trims to ensure I was good. Reset codes and it has never come back for over 5k miles.
Reset your codes and run it. Everything you reflash the ECM the codes might come back. Mine has come back every time I retune the car but I goes away after clearing them.
To the OP,
I had the same issue with my airaid intake. Installed and then got the same codes only during stop and go traffic. Reset the code and came back one more time. Check the fuel trims to ensure I was good. Reset codes and it has never come back for over 5k miles.
Reset your codes and run it. Everything you reflash the ECM the codes might come back. Mine has come back every time I retune the car but I goes away after clearing them.
Thanks
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
OK thats great so why in hell would GM think I would want to tamper with it? but I may need to replace it . This is as crazy as the SAE, Metric bolts and nuts problems, aye yie yie !
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,206
From: Raleigh, NC
St. Jude Donor '15
Yeah look at it up close and see if it's 5 point or 6 point first...
There is basically every combination you can think of of 5 point, 6 point, torx, torx plus, with and without tamperproof
If you can at least narrow down how many points it has then that should narrow it down to either torx or torx+, and if whichever you already have isn't fitting then you know it's the other one.
Burning Brakes
Joined: Dec 2014
Posts: 959
Likes: 24
From: Los Angeles, CA
Sorry I can't elaborate a lot more on fuel trims but I know other members will chime in with more knowldge. All I know is that there are two set, short and long term. Long term stores the values and short variate as you drive.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
so I bought a 5 point torx set on ebay and swapped out the Maf sensor but same problem so I put my OEM air filter back in have had no codes so far seems to be the K&N filter flows too much air?
Anyway I have an appointment for a Dyno tune and will install the K&N for the tune.
Anyway I have an appointment for a Dyno tune and will install the K&N for the tune.