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Discussion Starter #1
So I've searched some ancient threads and found that several people had this problem with several different intakes as well as several different solutions..

Just looking for the "end all" to mine...

Basically, I installed a K&N Typhoon on my 06, 2.2 on Friday... Tuesday morning CEL came on. Got it checked p0171 system too lean...

So I checked all of my connections, tightened everything up... etc... reset by way of the battery... and it came back on this afternoon on my way home...

So Assuming there are no leaks... what do you guys suggest?
 

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They started using the secondary air intake at the end of 06. Do you know if you have this and if your intake is set up to accept it?
 

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You would have this tube if you have SAI secondary air induction.



---------- Post added at 06:26 PM ---------- Previous post was at 06:21 PM ----------

How many miles did you put on the car after changing the intake? The ECM should re-adjust for the extra air on it's own within 20 miles or so or 20minutes unless it's already at its limit.
 

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Discussion Starter #5
I don't have that extra tube on mine... And I'd say I probably put 100 miles or so Before the light came on.

And the 2 times it did come on were 65mph 5th gear cruising speed, no throttle fluctuation at all when it actually lit up.
 

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I don't have that extra tube on mine... And I'd say I probably put 100 miles or so Before the light came on.

And the 2 times it did come on were 65mph 5th gear cruising speed, no throttle fluctuation at all when it actually lit up.
Does your intake have an extra barb, if the intake was made for no SAI than it would have been for 05 and up not 06 and up. Of course ads are worded to fit your application now a days.

Is the hose between your valve cover and the intake conected properly?
 

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I probably put 100 miles or so before the light came on.

And the 2 times it did come on were 65mph 5th gear cruising speed, no throttle fluctuation at all when it actually lit up.
Your car is now inhaling more air and somehow your "PCM" hasn't been able to correct for it. @ least not yet. This is a long shot but try disconnecting your battery for 15 minutes, this should reset the "PCM" data matrix and it will have to relearn all the sensors. It might run a little funny at first but it should fully correct itself on it's own within 20 minutes. If this doesn't work you might need a tune.

You can always put the old one back for testing to see if it is really caused by the new air inlet.
 

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What if the MAF sensor is just reading the flow crazy and that is messing it up?
 

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Discussion Starter #9
No extra barb and I've checked all connections... will do again... just wondering if By coincidence it could a O2 sensor issue... but just seems that it has to be coming from the intake as it has been so recent.

Might get some MAF cleaner too and try that... I've heard stuff about the oil on filters and such.

---------- Post added at 06:23 PM ---------- Previous post was at 06:21 PM ----------

You can always put the old one back for testing to see if it is really caused by the new air inlet.

I'd hate to... lol, but if I can't figure it out, I will.
 

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What if the MAF sensor is just reading the flow crazy and that is messing it up?
He would get a "MAF" code, he's getting an HO2 discrepancy. This means your HO2's are working fine.
 

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DTC P0171
Circuit Description
The powertrain control module (PCM) controls the air/fuel metering system in order to provide the best possible combination of driveability, fuel economy, and emission control. Fuel delivery is controlled differently during Open Loop and Closed Loop. During Open Loop, the PCM determines fuel delivery based on sensor signals, without heated oxygen sensor (HO2S) input. During Closed Loop, the PCM adds HO2S inputs and level of purge to calculate the short and long term fuel trim adjustments. If the HO2S indicates a lean condition, the fuel trim values will be above 0 percent. If the HO2S indicates a rich condition, the fuel trim values will be below 0 percent. The short term fuel trim values change rapidly in response to the HO2S voltage signals. The long term fuel trim makes coarse adjustments in order to maintain an air/fuel ratio of 14.7:1. A block of cells contain information arranged in combinations of engine RPM and engine load for a full range of vehicle operating conditions. The long term fuel trim diagnostic is based on an average of cells currently being used. The PCM selects the cells based on the engine speed and load. If the PCM detects an excessively lean condition, DTC P0171 sets.

---------- Post added at 07:33 PM ---------- Previous post was at 07:30 PM ----------

Action Taken When the DTC Sets
• The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

• The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
• The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.

• A current DTC, Last Test Failed, clears when the diagnostic runs and passes.

• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.

• Clear the MIL and the DTC with a scan tool.
 

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Discussion Starter #13
Updating....

It turns on and off... randomly, If I'm driving around town... It will turn off, It's only running down the highway on my way to work... stopping for breakfast, then returning to the highway... It trips back on every time it seems...

So could it just really be Too lean in 5th gear after a long period of highway driving? What could I do to eliminated this? I was thinking about making a restrictor plate to go in behind the cone...(I work in a fab shop)

Thoughts?
 

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Kinda defeats the purpose of adding an intake though, unless you mean to try and see if it will eliminate the code. Just wrap a plastic bag over part of the filter to see if it stops the "CEL" from coming on then you'll know for sure if it's your setup. I still think you have a vacuum leak somewhere causing this. Check your fitment again.
 

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code po171,system too lean

i have a 2007 2.2 coupe 5 speed started getting this code in the last week, i have a scanner and it trips the code parked at idle 0mph and 850rpm roughly never while driving, any thoughts would be appreciated thanks!!!!
 

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Have you checked your air filter? I know it seems to be the opposite of what you'd expect but as filter gets dirty the "ECM" will lean out the mixture as your throttle needs to be depressed even more for same idle speed. Not always logical but worth checking.
 

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Hope the air filter turned out to be the cause, turbolover119! And welcome to the forum! If I can check into any warranty or recall information for you, don't hesitate to send me a private message with the last 8 of your VIN.

Sarah, GM Customer Service
 

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air filter is as clean as a whistle, sorry i can't send a privite mess. yet i dont have enough posts lol

---------- Post added at 05:52 PM ---------- Previous post was at 04:50 PM ----------

i have developed a slight exhaust leak recently, could that possibly be causing the code?
 

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There is a hole on the intake where that secondary induction would go and it sucks extra air thru it causing the lean code I hade a the dealer plug it with a rubber cork and it has not come back since
 
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