P0171 Lean Code just Popped Up
Thread Starter
Racer
Joined: Apr 2010
Posts: 384
Likes: 9
P0171 Lean Code just Popped Up
No recent mods to the car.... 2008 with lg pro longtubes (no cats, plugged rear 02's). Intake is the killer bee ii with beehive. Car has a full dyno tune using HP tuners and has been running GREAT. Other than the CEL, you wouldn't know anything was wrong.
I'm just getting the single code, the long tubes have been installed/tuned for about 2k miles with no issues.
The only thing it could be would be one of my front o2's ****ting the bed?
I'm just getting the single code, the long tubes have been installed/tuned for about 2k miles with no issues.
The only thing it could be would be one of my front o2's ****ting the bed?
Team Owner
Joined: Sep 2005
Posts: 20,352
Likes: 568
From: Ventura County, Calif
Did you recently get gas?
Check the gas cap first, the CEL may clear itself. Or could be bad gas which was a prevalent problem with '08's early on. Just FYI here's an '08 thread for info. Good luck.
http://forums.corvetteforum.com/c6-c...and-p0174.html
And another one for info:
http://forums.corvetteforum.com/c6-c...ep-inside.html
Check the gas cap first, the CEL may clear itself. Or could be bad gas which was a prevalent problem with '08's early on. Just FYI here's an '08 thread for info. Good luck.
http://forums.corvetteforum.com/c6-c...and-p0174.html
And another one for info:
http://forums.corvetteforum.com/c6-c...ep-inside.html
Thread Starter
Racer
Joined: Apr 2010
Posts: 384
Likes: 9
First thing I checked was the gas cap just to be sure, don't think the car is running poorly as I just recently had a chance to really get on it and couldn't hear audible knocking.
Also, it's just the single code, not both.
Also, it's just the single code, not both.
Tech Contributor
Joined: Mar 2003
Posts: 12,094
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
The tune needs a tweak of the long term fuel trends at some speed other than idle. This isnt always caught especially if its a dyno tune only and no street tune verification.
Race Director
Joined: Aug 2005
Posts: 13,592
Likes: 187
From: Hudson WI
NCM Sinkhole Donor
Thread Starter
Racer
Joined: Apr 2010
Posts: 384
Likes: 9
I just can't think this is it, the car has been driven and tuned for several thousand miles, why would it just now throw a code? Also, the intake Manifold is stock untouched, so I highly doubt that's it
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
Burning Brakes
Joined: Apr 2006
Posts: 1,059
Likes: 17
From: Stokesdale NC
That's exactly what happens to mine. The reason it might happen now after thousands of miles is that the air is cooler and denser, requiring more fuel but you run out of adjustment and throw the code. Mine does this when the outside temps are between 45-55F. Doesn't do it any other time.
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
If you can have a scan done by your tuner or someone with HP Tuners, it may help. Need to see the LTFT % Error and if it is only one bank or both.
Burning Brakes
Joined: Aug 2008
Posts: 802
Likes: 6
From: Oro Valley AZ
No recent mods to the car.... 2008 with lg pro longtubes (no cats, plugged rear 02's). Intake is the killer bee ii with beehive. Car has a full dyno tune using HP tuners and has been running GREAT. Other than the CEL, you wouldn't know anything was wrong.
I'm just getting the single code, the long tubes have been installed/tuned for about 2k miles with no issues.
The only thing it could be would be one of my front o2's ****ting the bed?
I'm just getting the single code, the long tubes have been installed/tuned for about 2k miles with no issues.
The only thing it could be would be one of my front o2's ****ting the bed?
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 3,665
Likes: 341
Bingo. Double check this. If you can find someone that has an evap smoker, get them to hook it up and see where the leak it. Popping a 0171 code is usually an air leak after the MAF. Unless there is something really wrong in the tune, I would go this route first.
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 3,665
Likes: 341
This will not cause a 0171 code, you will get a MAF performance error is the MAF is dirty.
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 3,665
Likes: 341
That's exactly what happens to mine. The reason it might happen now after thousands of miles is that the air is cooler and denser, requiring more fuel but you run out of adjustment and throw the code. Mine does this when the outside temps are between 45-55F. Doesn't do it any other time.
Thread Starter
Racer
Joined: Apr 2010
Posts: 384
Likes: 9
Again, don't think it's the tune, I watched the HP tuners on my final tune run and it had no KR across the entire pull at all, solid AFR's, and again, I ran for 2-3k miles after being tuned with NO issues, and the car ran strong as ever.
Could it not simply be a bad O2 sensor? The intake manifold is untouched, so I wouldn't think it would blow a seal, etc. just for no reason...
Regardless, haven't had a chance to get it to the shop, I'm swamped at work, probably will call my tuner/shop this week though I guess at this point.
Last edited by res0n0xg; Oct 20, 2010 at 01:33 AM.
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Again, don't think it's the tune, I watched the HP tuners on my final tune run and it had no KR across the entire pull at all, solid AFR's, and again, I ran for 2-3k miles after being tuned with NO issues, and the car ran strong as ever.
Could it not simply be a bad O2 sensor? The intake manifold is untouched, so I wouldn't think it would blow a seal, etc. just for no reason...
Regardless, haven't had a chance to get it to the shop, I'm swamped at work, probably will call my tuner/shop this week though I guess at this point.
Could it not simply be a bad O2 sensor? The intake manifold is untouched, so I wouldn't think it would blow a seal, etc. just for no reason...
Regardless, haven't had a chance to get it to the shop, I'm swamped at work, probably will call my tuner/shop this week though I guess at this point.
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 3,665
Likes: 341
Again, don't think it's the tune, I watched the HP tuners on my final tune run and it had no KR across the entire pull at all, solid AFR's, and again, I ran for 2-3k miles after being tuned with NO issues, and the car ran strong as ever.
Could it not simply be a bad O2 sensor? The intake manifold is untouched, so I wouldn't think it would blow a seal, etc. just for no reason...
Regardless, haven't had a chance to get it to the shop, I'm swamped at work, probably will call my tuner/shop this week though I guess at this point.
Could it not simply be a bad O2 sensor? The intake manifold is untouched, so I wouldn't think it would blow a seal, etc. just for no reason...
Regardless, haven't had a chance to get it to the shop, I'm swamped at work, probably will call my tuner/shop this week though I guess at this point.
I doubt it is either, and I doubt it is a intake seal, the factory seals are really good. I think it is a hose that either is loose or cracked. I have seen a ton of them cracked and they finally get bad enough where they will suck in air. As far as the tune, the only reason I said that is because of the temp change outside you referred to. Sometimes that is easy to not look at in the tune because you are no where near it, but now the car is in a situation where the ECT or IAT is in that range.
Burning Brakes
Joined: Aug 2008
Posts: 802
Likes: 6
From: Oro Valley AZ
Intermediate
Joined: Jan 2007
Posts: 49
Likes: 0
From: Raleigh NC
I had the same issue a after my car was tuned. The lean code appeared as the temp dropped. Also my exhaust tips remained clean after washing with the initial tune so I know I was running leaner, but no codes appeared in warm weather.
After tuning adjustment by a different shop all is well.
After tuning adjustment by a different shop all is well.
Last edited by speedaholic; Oct 24, 2010 at 09:01 PM.
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 3,665
Likes: 341
Justin