[RickD]

Getting a Supermod Tune, PTB & SuperSparx next weekend so I need to get this code fixed.

About 2-3 weeks ago, I put on a K&N Intake. All went well. At the same time, I put in new Delco Iridium Plugs. about 2-3 miles down the road, CEL came on, P0171. Checked all hoses, clamps, etc. and all were tight. Cleared code manually and rescanned, had Pending P0171. Then a CEL shortly after.
Spent a week trying to find a vacuum leak to no avail. Used Propane, Carb Cleaner, digital exams of all vacuum hoses. Nothing. Cleaned MAF Sensor, etc.
Next day replaced the factory Resonator box, cleared code and since then no codes.
Since this P0171 started, I've read what I think is every entry on the forum that has reference to P0171.
Today, I put the K&N intake back on and sure enough, within minutes, I had a pending P0171, then a CEL.

What am I missing? If all is working great with out the K&N, and a code with K&N, am I destined to live without the K&N Intake?

 

[08Canyon]

Would a bad O2 sensor cause this?
Is that code the lean condition code?

The only reason I ask about the O2 is maybe you have more air coming in and the O2 sensor is reading the result of what the MAF Sensor told it to deliver for fuel. Because the gasses it is sniffing is leaner (the result of more air and MAF not being told to increase fuel).

I don't now if that is exactly how the MAF and O2 work together, but maybe you do?

I know there are a lot of vehicles out there that throw codes with Aftermarket CAI systems installed.

Can't that be fixed in the tune, to remeter the fuel? I'm asking -I don't know. Or will the tune not work if there is a pending code?

 

[RickD]

Would a bad O2 sensor cause this?
Is that code the lean condition code?

The only reason I ask about the O2 is maybe you have more air coming in and the O2 sensor is reading the result of what the MAF Sensor told it to deliver for fuel. Because the gasses it is sniffing is leaner (the result of more air and MAF not being told to increase fuel).

I don't now if that is exactly how the MAF and O2 work together, but maybe you do?

I know there are a lot of vehicles out there that throw codes with Aftermarket CAI systems installed.

Can't that be fixed in the tune, to remeter the fuel? I'm asking -I don't know. Or will the tune not work if there is a pending code?

The P0171 is the Lean Condition Code for sure. I'm still chasing it down as a vacuum leak somewhere. Every piece of documentation I can find tells me that's what it is.
I suspect that because the aftermarket CAI is sucking in more air as you mention, it's going lean vs. the factory air intake because of a small vacuum leak. Just can't find it yet.
I don't know how the MAF and O2S work together.
Being retired, I have to do a lot of testing myself, SSI only goes so far. Sure would love to take it in to a shop and save the aggravation. - lol

 

[canada2005]

Just a basic thing here. Disconnect the battery and let it sit for a bit. Let the computer relearn everything again with the new intake.

 

[rshadd]

You have a vacuum leak!

 

[Az2006z71]

I can verify that when installing my K&N CAI that I unhooked the battery while installing it and the headers and never encountered a code. Most people that have, didn't disconnect battery for at least 10 minutes.

Sent from AutoGuide.com Free App

 

[limequat]

It's a problem with the K&N tube. Many of them do this. It needs to be fixed in the tune.

 

[RickD]

The latest..... so far, it's been 24 hours since I've seen a pending or solid P0171.
Yesterday am, I vacuum gauged the TB and got a 20 Hg on it. While there, I fuel pressure tested on the fuel rail and had 59+. Then vacuum gauge checked each vacuum line and each checked at 20Hg. Put back each and made sure all were as snug as possible.
Then with gauge hooked to the intake, pop the gas and dropped to 2-3 then bounced to 25 or so then back to a steady 20.
Only thing I can thing of is that something might have been loose or something that I must have over looked.
I've driven over 200 since yesterday am, highway, city, etc. Still no code back yet. Here's hoping.

 

[Supermodulation]

Glad to hear your getting good results.:th_woot:

 

[RickD]

Glad to hear your getting good results.:th_woot:

Me 2 James. This has been as weird as an electrical bug. Was a lot easier to build a circle track engine and drop it into an old hobby car for sure.

 

[Supermodulation]

Me 2 James. This has been as weird as an electrical bug. Was a lot easier to build a circle track engine and drop it into an old hobby car for sure.

Very true and I feel your pain. You are doing it the right way and get everything fixed and good working order before your tune.

 

[matt98]

Hey I'm going thru same thing. It's not vacuum leak. It's the tube . I called kn and took pics of the intake and they sent me a new tube. The new tube looks just like the one I had but it had different number. We'll got it on and I noticed it lowered my fuel trim. Still my long term fuel trim is staying around 23 once it hits 25 u get engine light. I just don't get why my short term fuel trim is staying -5 to 5 and long term staying that high when it's based off fan average of ur short term fuel trim. I've had check engine light come on one time since I've put new tube on. Also better gas mileage I was only getting lil over 200 a tank and I've got 06 crew cab z71 4x4. But u can email kn and they will send new tube to try. All u gotta do is take pics of it on ur truck and give them ur information. So the new tube does help but it still runs right on border of throwing light.

 

[RickD]

Thanks for the info about K&N. right now I have about 1200 miles on a tune I got from Supermod back on 4/19. Made a nice long round trip to Virginia from CT and not a code. I do not know what magic James worked to make it all go away. I too battled it for a while and never did find a vacuum leak. I'll have to see if I can set up a gauge in my ScanGauge and see what my fuel trims are at.