[GSXRider]

Hello,

My name is John and I drive a stock 03 F150 Supercrew Fx4 5.4L that I'm starting to do upgrades to, upgrades include K&N cai's, Magnaflow cat-back exhaust, Edge Evolution Programmer, 6" suspension lift, 3" body lift and 37"x12.5"x17" tires. Upgrades to this date are: K&N cai and as soon as I installed K&N drove in Perf mode, got PO171 & PO174 (Adaptive Fuel System Too Lean Bank 1 & Bank 2). Would like to run in Perf. mode due to the increase in tire size and lift, but not sure what to do... After discussing with Edge support, they said I should contact you for custom calibration.

Ahhh, so many questions, so I'll try to keep it short...

1) If I would have run it in Perf Tow mode, would I have been less likely to have the DTC's show up?
2) Would me running 87oct instead of 91oct in Perf mode be the cause of these codes showing up?
3) What do you feel would be the appropriate mode to run in for the increase in tire size and lift?

Not sure what to, but because of the increase in tire size and lift I purchased the Edge Evo hoping to compensate for any loses, will you help me with my confusion?

Truck currently getting lifted, should be done by Wed. 5/12/10 will send Pics

[88Racing]

Welcome!
Nice looking truck!
Here's some possible answers to your codes.
Causes
A code P0174 and/or P0171 may mean that one or more of the following has happened:

The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters can cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.
There could be a vacuum leak downstream of the MAF sensor.

Possible Solutions

Possible solutions include:

In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
Inspect all vacuum and PCV hoses, replace if necessary
Check for a dirty fuel filter and proper fuel pressure.

[GSXRider]

Thanks 88,

Cleaned MAF, still getting DTC's, but will try checking for vacuum leaks and replacing the fuel filter, thanks again

[cody994x4]

1) yes it would be more unlikely to get the lean codes....lvl 2 tow tune is richer.
2) running 87 on 91 tune is not good, dont do it...88 can tell u more abt this.
3)lvl 2 or 3 would b good to run w the 37's/lift unless u have a custom tune for your setup. however you will need to re-gear to a 4.56 ratio

hope this helps. peace

[GSXRider]

Thanks Cody,

That info helps, my Evo is really new and I haven't even used it for a week. Will try different modes for a couple of weeks and get back to everyone, but will still get Evo upgraded soon to Gryphon for Perf mode custom tune, Thanks!

P.S. New to all this Forum posting and threading, so bare with me everyone, hope I'm doin' OK!

GSXRider

[JackandJanet]

GSX, you definitely want to be in the Level 1 or 2 tunes if you have 87 octane gas in your truck. Level 3 is for high octane gas only! As Cody told you, Level 2 is a slightly richer tune and it may make all your problems go away. I also think you should seriously consider regearing. You are not doing your transmission any favors trying to turn those big wheels with the stock gears. Effectively, it's a bit like you're towing something when you aren't!

When Bill writes custom tunes for you he will adjust them to account for your CAI, which shouldn't be causing a lot of trouble on your model year truck, but the more I see about troubles people have with them, the more I wonder....?

- Jack

[cody994x4]

ive pretty much decided that if you have a CAI system, your not running right unless you have a custom to go with it. and if you have both, the benefits are small. gotts mod is just as effective and doesnt need custom tuning. im still planning on doing the gotts mod soon.

next weekend ill be putting a good 5-600miles on my truck. i plan on logging some MAF flow values, at given speeds. that will give me a 'base line' for any future comparison.

[Longshot270]

I would also run the 87 tow not just because of the CAI but because it will also help turn those tires better due to the increased tuning for torque.

[GSXRider]

JackandJanet Thanks,

Definitely considering the gear changing, not sure what to do , I mean I know to have the gearing redone, I'm stock at 3.73 but to what ratios. I'm a bit mechanically inclined, but definitely don't plan on doing it myself , do you or anyone listening have any suggestions.

[Longshot270]

4.56s have shown to be popular for 35s. You could either go with them or 4.88s if they will fit. The 4.88 should bring you close to the stock 3.73 ratio for 37s while the 4.56s will put you near the stock 3.55 ratio.