I have a 2G GS4.. Stock ECU, K&N FIPK Intake, Tanabe Hyper Medalion 'Catback'.. ever since I put the intake on, I have gotten a Bank 1 Lean code 3 times.. it happens LESS often than not, and I actually havent seen this code now in weeks. However, in my reading and research, I have come across a lot of info and posts regarding this, and THIS one has me a touch concerned:

I understand the whole air/ratio concept, and I know that lean is much worse than rich.. but they have been very rare, and only momentary. (On 2 of the occasions that the CEL came on, I scanned right away, got that code, and cleared it.. and it didnt come back for a while.) Am I running risk of damage to the engine, simply by installing this intake? Is there an upgraded MAF I should consider for my application? Or should I get an AFC Neo or what?

 

it really depends on you setup. I'm assuming that this K&N intake is the whole new tubing and wut not and not jus a drop. When i installed my intake i had also put in a breather filter for better throttle control but ended up getting that similar code. I'm not sure bout the recycling hoses or air hoses in general on the GS4 but i kno if any of those hoses that were normally connected to your factory airbox aren't reconnected to the intake pipes then u will get a code and thats wat making your fuel run lean. i thnk that culd eventually damage ur fuel system but im not sure. if u capped any hoses or didnt connect sumthng u eith need to run it to the intake or get a 3-way splitter for it so the code doesnt come bak up

 

Im running the K&N FIPK kit, which IS the full tube, section-off wall, etc. All of the factory hoses that connected to the original airbox are still connected to the tube. No breather filter installed, still getting breathing from the intake pipe.

Would post a pic but Im at work..

 

Thats interesting. I have the Weapon R, full pipe and i have never not once thrown code. It shouldn't be any different for yours.

Did you clean the TB and the MAF when you swapped? How is the idle?

Also as BP mentioned i would go back and check your hoses but you would probably notice a much diffrent idle.

 

In for some answers. I was thinking about getting an intake and was hoping that it would just be a simple install with no problems later on, but this seems like it could turn into a huge problem.

 

Just get rid of that crap. Not worth the minimal gains you get. K&N's are garbage anyways. They let more crap into your engine wearing on your piston rings and also get crap all over the MAF.

Lean = Bad.

 

So whats better than k&n? injen? aem? I guess the preferred intake is the SRT one, but I dont want to spend that much on an intake, but I dont want anything thats of cheap quality either.

 

Listen, I also have the K&N FIPK setup and it IS the best bang for your buck intake. Especially if you should want to get an A/F tuner down the road. I had the SAME issues as you had a couple of months after I got my K&N FIPK intake. PO171 - engine bank 1 too lean.

1) Look for ANY vacuum leaks a hose perhaps isn't FULLY connected or not connected at all.

2) Your MAF sensor, located on the air intake tube could be dirty. A relatively dirty MAF with ALL stock components won't necessarily throw a CEL. Since there is a low amount of CFM flowing into the stock airbox there probably is an "error range" in the ECU to account for a dirty MAF sensor for the car to still run properly.

However, now that you have added something that brings in A LOT more CFM (air), if the MAF is in fact dirty it will more likely NOW throw a CEL code because that "error range" is gone. ***Clean the MAF sensor with CNC Mass Air Flow sensor spray.***

3) When all this is done disconnect the negative battery terminal and let it sit for at least 1 hour. Re-connect and start...let idle for 5 minutes before you drive. Kind of sucks but by doing this all you radio presets and seat memory get deleted; you must re-enter them.

Do all of these and I bet it fixes your problem...GL!

 

Good deal.. I have been thinking about cleaning the MAF, although I havent yet due to the very strange shape of the MAF housing! lol Used to seeing an exposed element, not what looks like a plastic bullet with a hole in it.. :/

I have some of that CNC MAF Spray, so I will try that and post an update. I definately didnt locate any vacuum leaks, and all looks well with the hoses. Just wanted to see what the 2GS community had to say about it first.. I like hearing from people who have already experienced things..

Also, just clearing the code, and pulling the ECU fuse for a while will accomplish the same thing as disconnecting the battery.. only it will save yer radio presets and seat positions!

 

Make sure when you clean the MAF that the battery is unplugged and the harness is disconnected from the MAF. A couple of sprays inside that hole and you should be good to go.

When you installed the K&N FIPK did you re-set your ecu? By either pulling the fuse or the neg battery terminal? If you didn't then that's what you need to do and that's all!

 

I didnt.. but I think Im going to clean the sensor AND reset the ECU anyways, just to be thorough and safe! Thanks for the feedback man! Glad to see someone reads this ***** and is willing to throw some 2 cents in to help someone out!

 

Hey DJ420 -

Any luck with this? My GS350 just start throwing the same lean codes. Lexus says to put the stock intake back on or they can't really support it.

I was going to get the CNC to clean the MAF and see how that works.

Any update on this from anyone else?

thanks,

Amir

 

Umm..maybe you want to try the 3rd Gen section..IDK

 

Check for vacuum leaks, make sure bank 1 sensor 1 oxygen sensor is working properly, and clean the MAF. Give it a try.

 

its the intake. Same reason I got rid of my SRT. The gains will be minimal, and you will get a lot of look at me noise. Had similar problems, took me 3 days of messing around with friends GS parts to figure it out. His Maf, my SRT still installed, still had problems. Took out SRT, his maf car ran and idled much better. Took out intake, replaced Maf, ECT and PCV valve, all good.