His morning I ordered my edge Evo tuner and a k&n FIPK cai and I've been reading my truck might run lean is this true? And if so why?

 

Hi. Without a custom tune, the CAI may cause your truck to run lean because the PCM operates the air/fuel mixture in a range that will be too thin for the new amount of air the intake will provide. Furthermore, the "drive by wire" system has an inherent fuel delivery delay, which also can be corrected with a custom tune.

I have always kept this mantra regarding CAIs and the stock 3V 5.4L: More than likely it is best to wait until you can get a custom tune before adding the CAI. You will find yourself missing at WOT occasionally. Some folks on here somehow pull it off without a hitch. I tried the K&N intake and was missing all over the place, but I still have the original 2004 PCM strategy. Perhaps the fortunate ones have the TSB update? Either way, a custom tune will fix all of it... Best not to add the CAI until you have compensated for the thin air/fuel mixture range and the fuel delivery delay. Or drive very controlled wilst in taking your "cold" air lol. Good luck.

 

How will I know if I'm running lean will the edge tell me a code or something?

 

There is a good chance that you may not throw a lean code when you are in fact running lean. I would get the custom tune lined up before you run the CAI... But it is possible to run a CAI on the canned tow tune while you wait... The lean condition can be hit or miss depending on your model year and PCM stock calibration.

 

I don't have the edge, I have a SCT X3 and I don't get any data unless I'm plugged into the ODB. The truck should throw a CEL and I think you can use the Edge to check the code. Reference the code online and you would see something to the effect of "lean bank 1 or 2, etc".

You would have to running lean for a long period of time for that to happen though, i.e. a minute or more.

The "lean condition" associated with CAIs is usually a very abrupt, but profound lean condition - which is why the miss usually occurs on WOT. The air flow into the combustion chamber is so fast and so big, that the fuel delivery cannot keep up (because the stock PCM strategy can't measure that airflow and sets the fuel delivery to the max, but it still isn't enough). This will cause you to burn lean, but only for a few seconds (if you let off the gas everything will normalize).

So it's hard to answer your question without a diagnostic tool monitoring your air/ fuel mixture across a meaningful amount of time while driving. The CAI should cause the lean condition abruptly and this manifests itself in a misfire or a bog down of the engine. Jumpy throttle response and a sudden loss of power and the CEL will all indicate a misfire. Too many of these and you have to start worrying about your cats because you are essentially dumping raw gasoline into your exhaust system... This is why in my opinion don't even mess with a CAI without a custom tune on these trucks. The canned Edge tunes are set up for a stock intake. If you have custom tunes, make sure you ask the person who wrote them if they accounted for the fact that you have an intake so they can:

A.) widen the range of possible air volume into the engine
B.) eliminate the fuel delivery delay from the drive by wire stock strategy

Hope this helps.

 

Doesn't really have anything to do with air "rushing in too fast" and the lean CEL is not set until a 19:1 a/f ratio is met. So a CEL is only a indication of a terrible lean condition, lower 16:1 a/f's are still dangerous. OP read this:
https://www.f150forum.com/f7/edge-mods-93740/