riding_in_debt

I've heard this a few times already through power programmer threads saying the 5.4L runs lean. I don't see why it is so does anyone have actual proof of the 5.4L running lean? I've heard not to run the programmer with intake and exhaust upgrades. If the engine was running lean then you will see that in the plugs. ive done plug checks and don't see signs of leaness. Also the MAF sensor would pick that up and relay that to the injectors, that's what that sensor is for to read air flow and the computer adjust the injectors accordingly. Also the o2 exhaust sensors will pick up if the engine is too lean. I would like to run intake and exhaust mods with my programmer but this issue has raised an eyebrow. My guess is someone in the past had a programmer but also had say an intake leak running the engine lean and possibly bad o2 sensors or just forgot to mention those sensors read it was lean. and a mechanic told them not to run a programmer or mods till the intake was fixed? rumors spread that why and that's commonly how myths start. So does the 5.4L actually run lean and I'm just not seeing it?

MOTOunplugged

Do a search and you'll see that it has been said numerous times that this will cause lean conditions. From what I've read is not such a significant lean that the computer will detect, but enough to damage your motor over time. Better safe than sorry.

shadowrider

Are you running the stock intake?

techrep

iTrader: (1)

Yeah...I didn't see it either...I ran a CAI for 25K ...no lean signs.

kevhead75

I believe the lean issues are mainly with the 04 models and maybe 05. Just because the CEL is not lit does not mean it isn't running lean. I can tell you for sure when I put my a CAI on my truck that it threw a CEL for a lean condition. Anytime you change the location of the MAF sensor or change the amount or flow of the intake air you should tune for those changes. You will get the most benefit from a CAI if you are tuned for it.

riding_in_debt

I did a little deeper reading and found majority of the problem being with 04' and 05' models bc the MAF systems were running a MAS system. From what I found the 04' and 05' doesn't have a MAF metering system that allows the computer to adjust automatically to air adjustments. It is set for stock conditions only. This post was found on f150online.com in 04' if anyone has read it, it has good info. But bc it was from 04' 05' it doesn't say whether or not the problem was fixed.

techrep

iTrader: (1)

Well...if it's running lean and the computer don't pick it up and throw a code for it...it must not be that bad, or as stated above my 08 has a MAF and it corrected the air flow as needed. Now ...another question is I installed level 3 on my Edge and have been told that the program advances the timing and thats why you need to run 91/93 Octaine...what about air flow for that ??

riding_in_debt

My truck is an 06' and I've been running my programmer with 2 degrees advance timing for better mpg and performance and still haven't seen a lean issue. What your saying is exactly what I said I didn't want. It has been said numerous times there's a lean issue but nobody really gives much proof or numbers. It's what one guy says to another that you shouldn't. The whole "better be safe than sorry" well nobody really knows why. That's like i still hear people saying only rotate your radial tires to stay rolling in the same direction. Well that hasn't been an issue with radials since they started making them bc of the way the cords were ran. New tires doesn't matter left right front back but people still say don't do it. I'm trying to find hard facts of why this engine does this. Saying the computer doesn't read it bc its not significant enough, when you do a physical check of the plugs and do a cut plug, there's no signs. If your running lean then your running lean. The computer sees very small adjustments in exhaust temp picked up by the o2 sensor. In 04' 05' the computers did flash codes of leaness when CAI's were installed. Has that now been fixed?

riding_in_debt

older engines the timing use to be retarded for emission reasons, so advancing the timing increases horsepower and economy. im guessing its still the same way so level 2 and 3 have advanced timing to increase power. I have mine on level 2 with 2 degrees advanced but i should just run level 3 and call it a day. im still playing with it and tuning it for economy and ive heard level 2 is better for economy instead of strictly power. but thats my reasoning for the post im seeing if anyone has facts.

the timing is just that, timing when the cylinder is at tdc on compression. your still pulling in the same fuel and air so advancing the timing is just tuning the engine better disregarding the emission setting ford sets stock. the programmer i believe runs rich (adding more fuel) and increasing the timing hence running 91/93 bc there's more volume now it needs better octane to keep from pinging. the programmer should be set to run well with the amount of air available since that's a fixed variable. thats partly what im looking for is what it is doing exactly. if ford has fixed this problem i found of the04' 05' not adjusting to increased air, then we should be good to do mods if we want to intake, exhaust and programming bc the computers should adjust themselves like in previous years of efi systems

token

Why not eliminate the guesswork and just install a wideband sensor and gauge?