I don't think your 100% accurate. I have K&N alone charcoal delete and NO ISSUES. I think you did not have them installed well and you did not grease properly. They do have to seat properly. Good luck and glad you have no CEL now but what a waste and shame that you can't use your K&Ns.

 

Ive put in K&N filters and removed my charcoals prior to getting a tune, never had CEL.

 

This happens sometimes in US spec cars. As the sensor in the intake requires leaner air. When you remove your charcoals, you will slightly have richer air entering the intake, and thus a CEL will pop up. IT all depends on what type of air box modification and the type of filters you use. Anyhow, with a proper tune, that problem is invincible.

 

Not quite.

A more free flowing intake can cause a lean state in the Air/Fuel mixture, because more air would enter the mixture. Adding fuel, can richen the mixture.

 

Here is one for you guys...

Why then when I opened up BOTH my air boxes I only had right sight charcoal and an empty, open-up with no lattice to hold a charcoal airbox on the left? Anybody realize they only had one charcoal filter?

 

What????? That's nuts.

Just a mistake from the factory.

Edit: did you happen to notice if the actual airboxes had the same air inlet as each other, as in, were the ovals with the MAF's inside the same shape?

 

Very good question!

My right side with the charcoal filter had the lattice and smaller hole and the right side(driver side) had no filter, no lattice, and larger hole! I think its a "FACTORY FREAK" (see older Propain and Jon threads)...LOL

So have no idea has this has been affecting my ECU and whether or not it has adapted or if my ECU was European Type??

 

One of your air boxes had no filter at all? As in, no charcoal and no air filter?

I've seen the older threads. haha

 

Both had large main orange filter but only one side charcoal. wierd....

 

Yes, strange.

 

As i stated, you will have richer air going into the intake. The air boxes from the US spec cars are so restriced and have charcoals to ensure that clean air enters the intake(emmision law). I'm not talking about fuel here. With a proper tune, it shouldnt be a problem and you can change your airboxes and filters without having a CEL.

 

The charcoals have nothing to do with air entering the intake. They are installed to reduce emissions escaping from your intake system when your car is turned off.

Air is not classified as "rich" or "lean". Air is air. The amount of air in relation to the amount of fuel and octane of fuel being used is what determines the air/fuel ratio and, thus, whether the measurement is rich or lean.

The air entering the intake stream on the US-spec cars is not "so" restricted, it is slightly more restricted than the ROW.

You can change your airbox and filters without a tune and not see CEL's as well. I have done this without seeing CEL's ever.

 

That would have zero effect. That is pre MAF.

 

Other vehicles I've seen get this code after K&N filters is caused by oil from the filters getting on the MAF sensors.