[mrttripled]

I just put in a Airaid CAI and the difference in sound was worth it. Mine didn't require a tune, so i shouldn't have to worry about any damage to the engine, is this right. Will the dealer give me a had time if I leave it on for warranty work?

 

[rupertajm89]

Tuning foe CAI's

TLR: where do i find a tuner for 2013 subaru?

I Love working on all makes and models of cars. In this situation right now i am working on a 2013 subaru Inpreza 2.0 I (my graduation present from college. and i bought myself a cold air intake. installation went swimmingly. no vaccuum leaks sounded great the air flow sensor mount fit. however the next morning the check engine light went on. i had code read and reset by autozone " too lean bank 1" next day code came on again. where would i find a tuner. i thought engines were automatically supposed to adjust the F/A mixture for the proper air level. the pipe is slightly larger than the stock. requiring a reducer to be used right at the top of the engine. it is spectre brand. so where can i find this magical tuner, and how does it work?
if you need any other information contact me at rupertajm89@yahoo.com

 

[Muckerpuck]

What makes you think the guys on an american ford forum know about an import subaru. Maybe you should find a subi forum before you blow your car up. Google it.

 

[benleonheart]

I ran into some issues running no-tune on my CAI.

The car would sputter and misfire, (Even got misfire codes)

Returned to stock and no more codes, no more roughness.

Get a tuner. $300 peace of mind's worth.

 

[JBert]

So long as the CAI inlet diameter is the same as the stock one, there won't be a problem. The MAF sensor is calibrated for a certain volume of incoming air, so if you monkey with the inlet size, the MAF has no way of knowing it, and you'll run lean. The CAIs that don't require a tune provide the extra HP simply by reducing the amount of drag, allowing the engine to breath easier. The stock filter setup has all kinds of twists, turns, angles, and other restrictions.

~HA

There still seems to be some confusion about this MAF and tune thing, so I'll try again. Heavy Armor mentioned it above . . . here's basically how it works, as I understand it:

The computer "commands" the right amount of fuel from the injectors, based on how much air is coming in. It knows how much air is coming in from the "Mass Air Flow sensor" aka MAF. The MAF basically measures the velocity of the air coming in; then the computer has to do the math to get volume and mass from velocity; to do this it needs the area of the tube. There is a "calibration" in the computer for the diameter/area of the tube. When you increase the diameter of the tube, that increases the area, so the computer needs to be told about this (aka "recalibrated") or it will do the math wrong; it will think there is less air coming in than there actually is; it will command the right amount of fuel for the air that it thinks is coming in; that won't be enough fuel for the air that is really coming in, and that's why the car will run lean.

So, if you replace the stock intake with a new intake that has a bigger tube, the computer MUST be recallibrated, aka "tuned", for the new intake size, or the car WILL run lean. Running lean like this can be very bad for the engine, don't fool yourself to think it is a good thing.

The reason some aftermarket intakes do not requre a tune is that the tube is the same diameter as the stock one. This does NOT mean that those intake are no good; there are several sources of restriction in the stock intake and the diameter of the tube is only one of them. That said, bigger is usually better, up to a point.

Ford and dealers are right to be concerned about aftermarket tunes, because they have no way of knowing if the tune is safe or not, because it can mess with many things. For example if the tune advances the timing too much, it can cause pinging/detonation which can be very bad. Generally they should not be too concerned about an intake alone, because that is pretty straight-forward (as long as it does not require a tune.)