'06 exp lack of power

[2.5gl]

2006 expedition, 4x4, 65,000 miles.
Problem getting engine to run well over 3/4 throttle, 3000 rpm and above. Not very noticeable in normal driving, however, towing a 7000# (8600# Max towable weight rating) TT to the coast proved difficult at best in the hills. Scenario: climbing 8% grade, in 2nd gear, 3500 rpm @ roughly 50 MPH, there is nothing left. Engine misses, looses power if pushed.

Fuel filter replaced with OEM 10K ago, oil changes every 5-6K at local dealer, nothing else ever noted by dealer.

Anything else that should be checked? Known problem for others? Again, this is a repeatable, consistant problem with and WITHOUT a load.

Thanks in advance to all!
Lewis

 

[Stoned06]

Coil packs could be going bad. The TPS (throttle position sensor) and the MAF (Mass airflow meter) could also need to be adjusted/cleaned/replaced. If it is truly a miss, I suspect coil packs. If sluggish, MAF and TPS are more suspect.
Just a thought, but are your adjustable pedals (if you have them) all the way down? It is a known issue that you will not get enough pedal depression for top end performance if the pedals are all the way down. Doesn't sound like your issue, but you never know.

 

[2.5gl]

I doubt pedals are the issue. It feels like a fuel cut situation, although I am nowhere near redline. I have yet to remember to bring scanner home from work to check codes, even though Engine light is not on. Are there specific values with the air flow meter and TPS I should lok for, or just the standard sooth sweep of resistance/voltage for the TPS and no big jumps in MAF reading while driving? It is scheduled to go in for a Tranny service and perhaps another fuel filter. Ford Dealer may have answer. If I get nowhere there, I will try on my own to resolve it. Going on another 250 mile trip in just over a week, want to straighten this out before then.

 

[Stoned06]

The MAF can be cleaned with carb cleaner. The TPS is actually built into the throttle body on the 3V engines so that is hard to get to to determine a value. I know how to do it on the 2V engines, but not the 3V. Could be the same? Typically the target value for adjustment is .98V, but up to 1.00 is OK.