EXACTLY! This is exactly why I'm saying that something is wrong, a leak or something.

If all this were just because you put on a new filter and the ECM doesn't like that it's flowing just a touch more than stock, then people would be setting codes left right and center when their stock filters got dirty and airflow dropped a bit. Obviously that doesn't happen. The ECM can very easily cope with slightly more or less air IF there's no problem. So clearly there's a problem here.

I'd be willing to bet that if you pull the airbox assy all apart, put it back together very carefully, paying great attention to making sure it's all sealed up fine, and then pull the battery for 10 secs, you will not see this again. But hell, what do I know...

 

I was running lean there too for the longest time. My air intake tube came all the off on me (note: I have not installed any kind of new filter or anything to it), so check and see if all your stuff is tight. BTW I dont know if this contributied to it or not but I had a bad Cam Sensor, which I dont know how that happened.

 

DanM you are correct a vacuum leak could cause that code, but given the current situation of replacing the air filter with a high flow version I think it's reasonable to attribute this code to the fuel trim levels.

I dunno if you have access to the manual but short term trim levels being more than 10% off the long term levels will cause this code.

 

Yeah I know what causes the code. I suppose it's possible, but I'd bet good money that this is not just due to a new filter. Like I said above, if that were true, this thing would set codes out the butt when you replace a dirty air filter, and it doesn't.

I hear what you're saying, but if all this guy did was replace the paper filter with some other brand, and locked it back inside the stock airbox, theres no way the airflow is that much different. ESPECIALLY when he's only had the car for a week, and the LTFTs probably aren't even in equilibrium yet! Not even Ractive filters are that special. I still say small vac leak.

All other discussion aside.... why WOULDN'T you take the 10 minutes to take the tubes off, and put them back on just to be safe? You'd rather drive around with (possibly) a vac leak and leaner than normal condition just because you're too lazy to check?? Just take the tubes off, put em back together carefully, and clear the code. It takes 20 minutes man.

 

Dan, there really is no way to have a vac leak, there is only 1 connector to the TB pipe and it is rubberized, the PCM is seeing a LOT more airflow that is pushing it outside its realm of compensating. We datalogged it, the MAF readings went WAY up real fast compared to stock. sorry to say Vac leak in 1 connector, not likely....to easy to say, the airbox and up pipe are 1 piece, ther is only 1 clamp that connects the up pipe from the airbox to the tb pipe.

 

Bingo, Mr Goodwrench...this is not a high flow filter in the stock canister, it is a conical air filter attached to the stock box with the bottom left off....

So the airflow is a LOT different, you do read that we datalogged both and found a lot of difference not to mention S/C pressure is up .5 lbs and spools(funny to say, I know it doesnt spool but with the bypass it does in a way) WAAAAY faster, you can flash full bosst I'd say a great deal faster than stock...not trying to be smart just clarifying
oh and trust me we checked the reinstallation well

 

OK, I'll take the hose off the TB and take off the other end too and recheck everything. I have already checked the connection for the MAF and made sure everything was tight down below. So say if this doesn't fix my problem. Does that means it's my Fuel Trim? Do I have to get the dealer to fix that or unhook the battery? And if the dealer does it will they void the warranty cuz of the filter?

Thanks alot for all the help!
Dave

 

Fair enough, thought he said he just put a new filter in the stock box. Good luck, hope it doesn't come back on you!

 

I got the dealer checking mine too...I disconnected the battery and the code came back on. I got them too check for vacuum leaks, MAF and fuel trim levels...What is going too happen when we order our CAI like K&N Typoon and AEM...How do we fix this problem? Colin

 

Okee dokee.

I am just gonna interject with a little bit of sanity here.

Recheck all of your air intake connections, make sure the the clamps are secure and the pipings is seated properly.

There are lots of things that can cause a P0171 it may just be coincidence that it occured so close to the installation of the filter..

Make sure all of the pleats of the filter are even spaced, an irregurlarly shaped filter will disrupt airflow and cause false DTC's.

Make sure your ENGINE OIL DIPSTICK is fully seated in the tube and its seals are okay.

Make sure your ENGINE OIL CAP is properly installed and seal is ok.

Make sure all of the vacuum & emissions hoses are in good condition and properly secure at their connections

Chnage your fuel station, small amounts of water in your gasoline will cause this code

High levels of alcohol contamination in your fuel will cause this code(or mistaken use of E10, E15, or E85 fuel)

A clogged or mechanically failing injector will cause this code.

This condition could be present during high fuel demand due to a fuel pump that does not pump enough fuel, a plugged fuel filter, or a restricted fuel pipe.

Loose or leaking exhaust sytem pieces can cause this code.

Leaking intake manifold gaskets.

Leaking supercharger gaskets or supercharger housing.


The best course of action is to take the car to a competent mechanic skilled in the operation, diagnosis and repair of this vehicle and its engine and emissions control management systems.

 

Ok guys well I just got back from the GM dealership they diagnostic the car most of the day and found out it was a bad O2 sensor....Even with the stock filter it was throwing that lean code. So they ordered a new O2 it will be in on Tuesday...Hope this helps guys.....Colin

 

Hey guys, I checked the stuff you told me to and it all looks ok. I'll take it back to the dealer and see what happens. Should I put the stock filter back in or will they even notice?

 

Yes put it back to stock or they will blame your filter. I am sure they will look there.

 

OK, I put my old filter back in and since then my CEL hasn't come on since. It might in a bit of time, not too sure. Got an apointment at the dealer tommorow so we will see whats going on with this. I'll keep ya posted.

 

MAF sensor and K+N filter oil do not go together......the oil will contaminate the MAF wire causing it to read incorrectly.....this is very commong on all MAF cars using a K+N filter...............easy fix as all you have to do is clean the MAF wire using a Q-tip and alchohol

 

you should NOT ever use soapy water to test a leak in a vac system as it will get sucked in to the vac system use carb cleaner and if it leaks it will change the rpms never anything you cant put in your engine never ever ever

 

^^^ Good advice - about 6 YEARS too late though............


Gets my vote for Necrothread of the Month