N1ck

I've had my ROW air boxes for about 9,000km and I finally got the CELs. The codes I got were P2187 (system too lean at idle), P2189 (system too lean at idle), P0171 (fuel trim too lean Bank1), P0174 (fuel trim too lean Bank 2). I tried switching my air filters to stock from K&N, the engine light is still there. (I changed my air filters when I swapped the stock air boxes out) Anyone who's running ROW and ever got any of these? It's been really annoying because I can feel that the car shifts really uncomfortably.

shades

Hey N1ck, try cleaning the MAF sensors themselves. With something like a brake cleaner, or alcohol. There might be some residual oil from the K&N's.

bhamg

Clean your MAFS, yes, but only use the spray MAFS cleaner commonly found in auto parts stores or a contact cleaner that leaves no residue and is plastic-safe (there are few like that sold over the counter at the usual stores where you would go). Nothing else!

cptdaz

Seems like most intake related CEL issues are airbox seal related.

BLACKONBLACKC63

Too lean= too much air or not enough fuel. If you have more air by installed ROW air box and the ECU cant adjust enough fuel, it will give you that code. I am highly rec get a tune. I have my ROW and Eurocharged tune and no problem so far. Good luck figure this out.

shades

An ecu can always compensate for the ups and downs of air flow...they just need the right info sent to them, hence the MAF sensors are sending back incorrect info, within the allowable specs...example would be dirty mafs, not trying to get into a technical debate but just the logical answer, giving that they were fine for 2 or 3 months on the car and decide to throw the same code on both sides at the same time.

HoozyerdaddyC63

Are they persistent CEL codes or one time light up?

I had a one time issue and the CEL went away the day before I was going to bring the car in to get looked at. My SA told me to wait til the light went back on and bring it in again.

In the end it ended up being a leak in the intake manifold. The replaced bolts, gaskets and seals under warranty.

Thrilla

I agree with everyone regarding cleaning the MAF sensors. I never had these issues when I installed my ROW airboxes.

The K&N filters are notoriously oily out of the box and most likely got oil to your MAF sensor. Get the aerosol MAF cleaner from any auto parts store, and clean the MAF sensors. Put back your stock filters or get dry performance filters instead.

I think the gains with replacing filters are minimal, except when getting a tune.

N1ck

Thanks everyone. I bought the cleaner today, will try that out and let you know what happens.

Yes, they are. I took my car to the dealership once and they couldn't find what was the problem until I told them I changed my air boxes, filters and they assumed that was the issue. So, they reset the code for me and it popped right up after 20 mins.

Rsquad911

Have had my ROW airboxes since car was new and have had no issues with a CEL.

What filters are you running? Oiled filters can gum up the MAF.... I am using AFE Pro Dry filters which are oil-less.

When you installed the airboxes did you make sure it was seated properly (filters and boxes)? When tightening the screws go in a cross pattern like you would with wheel bolts.

If you need a hand let me know.

DuaneC63

The ever so slight increase in airflow from a USA to a ROW airbox will not throw a CEL. More than likely you don't have a proper seal between the top of the airbox and the bottom. Take it apart, clean everything (including the MAF's) and reinstall. Your ROW airboxes should have come with new MAF's. If you're in doubt, swap the MAF's off your USA air boxes. You also need to clear the codes as they won't reset by themselves.

andrew c230k

its your K&N's causing the problem...

Multispeed

Had the same codes, it was the intake gaskets, replaced under warranty. Dealer said they have done a number of intake gasket replacements on the M156.

N1ck

Okay, I cleaned the MAFs . The boxes are sitting fine I think as I always tighten the screws in cross pattern. How should I reset the engine light? take it to the stealer or just disconnect the battery?

P.S. Do I need to clean the two black plugs as well?

Sincity

Take it to Autozone, Pepboys, major car parts retailer and have them scan and reset for free.

shades

Hey N1ck....run it by my shop and I'll reset it for you bro. If you want, I can do it in the morning. PM for the address

N1ck

Thanks Peter! Text or pm me your address please. When can I come by?

N1ck

I cleared the codes today and they came back later on at night... I'm getting really desperate. Should I try changing MAFs or should I be concerned about vacuum, manifold leaked?

Merc63

Take the car to the dealer man, you have warranty, use it.

Its probably a leaking intake manifold like everyone said. Its notoriously common and a simple fix.


Also check you have the air filter boxes securely tightened around the oval ports, if a tiny bit of air gets sucked through those joints after the MAF, it will throw the code.

Basically, you have an air leak AFTER the MAFs to throw that code.

Rsquad911

Could be a fouled O2 sensor?

Rsquad911

Hey Nick,

Did your set of ROW boxes come with an extra set of mafs? Try putting your old or new set in, reset the cel and see what happens.

N1ck

Fortunately yes, I've been trying to get the metal clips out, but it seems impossible... The bottom one is fairly easy, but the the top one I have no idea how to get it out. Do you have any tricks? Will my engine get damaged if the issues were to be either O2sensors, vacuum or manifold leak?

N1ck

I swapped the MAFs and it didn't help, so I decided to take her to the dealer and it turned out that my Weistec oil separator hoses got loose and the oil dripped into the intake. What an incidence... Fortunately, my SA covered up a story for me saying that the intake manifold gaskets leaked to prevent me from getting my warranty voided. For future reference of anyone come across these codes, try cleaning the MAFs first and if it didn't help, just take it to the dealer.

Roswell

Ur lucky to have a good SA.. Modding our engine can be costly when lil things like this happens.

P.S and don't mention ur dealership here, they might get into troubles. Lol

N1ck

Okay, I don't think that actually caused the problem cause my CELs popped up again later at night LOL