So Its been about 45k miles since I first put my K&N intake on. I finally bought a replacement filter, some cleaner, and a hydroshield.

I put the new filter and Hydroshield on and cleaned up the engine a bit, nothing too much. I didnt degrease the block, just wiped down all the dusty dirty areas.

Well I thought it might happen but with a new filter in place and the filter in the same position as the previous one. My fuel trims went up between 3.5-4.5% on average. You could say that my last filter is pretty dirty. I cant remember when I had the car tuned though, I though it was close to the time I got the intake. I dont know how much of an effect this might have, or if the filter is just constructed slightly different. Either way, im still within +/- 7% so Im okay with that. Id hate to have to get retuned for just this.

 

i thought you sold your cobalt a while back?

 

cudajoe can NEVER LEAVE!!!! Hell I still need to tune my car and I've had HPT for idk 4 years :/

 

clear fuel trims and restart mostlikey will end up around the zero mark again. its a calculated value and since more air is coming in it the maf should correct it to around zero on its own if you dont over a period of driving.

 

That's not how that works. It's based on the tune. Depending on fuel type and intake setup and other factors your STFT and LTFT can vary quite a bit. It will not be zero unless you are on factory tune and factory intake with 91 octane. Roughly.

With the K&N and filter wrap I range from 2.3% to 7% depending on weather and fuel.

 

if he was around zero before im assuming yes based on him posting about it, most likey the airfiler change. hell i had my airfilter of the car once and it wouldnt even start. very touchy on the intake sides. also if its high like yours at 7% at times may want to tune in a little more fuel or check for leaks. should always be low tuned of not unless your tune is soley using O2 sensor for fueling to keep it rich.

 

7% is not bad at all. Would be good to have a tune, but it's fine. Once you get into the 10-15% range you should worry. 15% regularly should set a CEL.

 

Yeah I was around 0 average with the really dirty filter, Im thinking when I tuned the car, the filter was dirty. Now I got a fresh filter on their and Im thinking the ECU is seeing more air flow and adjusting the fueling to compensate. im okay with it. Maybe I will try rotating filter positions again and see if it will change closer to a 0 average.

I never sold my car lol. I joked saying I did when my wife picked up a 2012 Cruze Eco.

When I do sell my car, I bet the next owners is gonna be pretty happy with how I left it. lol. I get such good comments on how well my car is holding up.


The drive to work today, the car felt more responsive and the engine sounded like it didnt have lung cancer. I will post a photo later of what a 45k filter looks like. So dirty.

 

How many miles on that dirty girl cudajoe?!

 

78k - seems average I think for an 09.

 

it should be 50... I only have 28k miles on my 2009.

 

75k is 15 per. That's where I'm at. I'd say 60k is probably average.

 

stop driving your cars in the winter!

 

Move farther south!!!!

 

In that 45k miles you didn't clean the filter any?

 

yup





Most of the chrome area was blackened by the layer of what looks like heavy amounts of brake dust, but my hand cleared most of that away. Took like washing my hand 3 times to get it off

 

I would have cleaned that thing at least a couple times there batman lol

 

That's not a dirty filter.... Ive seen filters from off road race trucks that ran a 300 mile up to the baja 1K on the same filter... And it was clean on the inside lol But you should be fine... Clocking your filter should have NO effect on the airflow as it should flow the same no matter what position it's in. It's normal for an untuned car to POSSIBLY throw a CEL.. Some do some dont according to them you can go 100K without needing cleaning.. The filter element/screen looks fine to me..


From K&N
4. How often do I need to clean my K&N air filter?

If you have not experienced a decrease in mileage or engine performance, chances are your filter is fine and does not yet need cleaning. To be more specific, the filter does not require cleaning if you can still see the wire screen on the entire air filter regardless of how dirty it may appear. When the screen is no longer visible some place on the filter, it is time to clean it. When used in normal paved road, street or highway conditions, our replacement air filters that fit in the factory air box should require cleaning every 50,000 miles and our large conical filters on an intake system should require cleaning every 100,000 miles. When used in dusty or off-road environments, our filters will require cleaning more often. We recommend that you visually inspect your filter once every 25,000 miles to determine if the screen is still visible.

 

I have both an stock and HPtune on two different ECUs. Havent plugged the stock ECU in for awhile. No idea where my trims are on that for the time being. There was a change and it may be due to a different filter and thats it.

 

You will be fine, You may see better mileage due to it breathing easier but that would entail using a light foot, lol 5% isnt much and is easily handled by the computer even if tuned for a set percentage/setup. It has tolerances that are acceptable. You can still see the screen part of the filter so it was not clogged just a little dirty. From what i got out of your post it's feeling better your just worried about you trims but are not throwing a CEL. Which if there was a serious fuel trim issue you would have a CEL/serious MPG issues which i have not seen so i say enjoy!

 

When you guys are talking about 7-10% fuel trims are you talking about LTFT or STFT??

 

Long term fuel trim.

 

Daaaang son....slacking