Have a 01 screw with a 5.4 It seems that when the weather turns warm, my truck runs like crap. The low end power from 1500 to about 2000 rpms is gone. This is the 2nd time. Dealer cant find anything wrong. Engine light does not come on. Now I gotta take it in again. I love my truck and have had fords in the past with no problems, but I am starting to have 2nd thoughts. My problem seems to be heat related. Also my little plastic throttle body cover looks like it has kinda melted, it is drooping, my temp gauge has never moved and I have been real easy on the truck. Anyone have any ideas? The dealer sure does not.
tp

 

I'd consider changing the thermostat to be in the 180-190 range. For some reason, it seems like your engine runs better at a cooler temp than most.

-Flea

 

I think it's the heat,mine has no power when it's hot out either. Good luck,,,98

 

Same here! I thought it was just me! Is your truck the LEV? I think that has something to do with it. Man this thing is fast at night, but when it is 100 here in SoCal, it is a pig!

 

Same experience here in the Dallas/Ft. Worth area. When the temp outside flirts with 100, I can definately tell a difference in power, especially at lower rpms. When I take the truck out in the morning, or when just starting it up, it runs great, but after about 10 minutes in the heat, performance suffers.

I thought it had to do with my K&N FIPK, sucking extremely hot air from the engine compartment when the outside temp is so hot. I'm considering modifying the system to a cold-air based set-up for this very reason.

Anyone have any solutions to this?

SlickWilly

 

I concurr with the above postings, these LEV motors suck, in hot humid weather
My 2000, even with all of its problems, ran better in hot weather, More of Fords Better Ideas....And what about the great fuel milage too..??

 

I thought I had a problem after the FANOF-150 rally... turned out to just be the heat and humidity... just runs poor at elevated temps. I believe it's the lower density of the air that causes this, but I could be wrong.

-Joe-

 

Should they not run this way? I am very disappointed in the "warm weather" perfomance of my truck!

 

My truck seems to lose some power in the hot summer temps as well.

 

i see now i benefit living in Iceland never hot here i´ve got lot of power you want some?

 

is anyone else having this problem?

 

i havent noticed a significant loss in power (well no more than is to be expected in 105° heat, based on my previous experience with my honda), but the truck is getting bad mileage (around 15 city, which isnt too good considering its a light truck and v6 manual).... this is same kind of thing that would happen to my honda (also LEV)... it would lose a little power, but would get really crappy mileage (26-28 city - not good for a hatchback weighing 2280 #'s). in the winter it would get around 32 city/38 highway. i havent really driven this truck in the winter since its been broken in, so i hope i get a 15% increase in mileage in the cold like i did with my civic.

 

Are you running the same brand of gas everytime you fill up? I've seen a difference in performance even between stations. Shell and Texaco seem to run best in my truck. And I know that the "formula" is different between states and even regions. California has a bunch of anti smog stuff in the fuel. I'm sure the heat doesn't help, either.

Maybe try a different octane/brand of fuel and see if it makes a difference...My $0.02.

 

Ahhh, finally something I can contribute!!!

High Density Altitude causes poor engine performance. The higher the density altitude, the thinner the air, the poorer performance. This is directly opposite of cold dense air, where our trucks (and most others) perform better.

Definition from AOPA online....

Density Altitude
Density altitude, a measure of air density, is not a height reference. Instead, it is used as an index of aircraft performance.

Air density — Determined by pressure, air temperature, and humidity, air density decreases with altitude, high temperatures, and high humidity. This means that any one of these conditions cause the air to be thinner than at lower altitudes, temperatures, or humidities.

High density altitude — The combination of high temperatures, high humidity, and increased altitude result in an increasing high density altitude condition. This reduces aircraft performance in all regards:

Engine horsepower decreases because the engine takes in less air to support combustion.
Thrust is reduced because the propeller gets less grip on the light air.
Lift is reduced because the light air exerts less force on the airfoils.
Also, at a specified indicated airspeed, true airspeed and groundspeed increase proportionally.

Hazards — The above factors cause increased takeoff and landing rolls and a reduced rate of climb. High density altitude is most hazardous when combined with heavy loads, calm winds, short runways, unfavorable runway conditions, and obstructions near the end of the runway.


As you can see, this is not an indication of a problem or misdesign on the Ford power train engineers. It's a naturally occurring phenomenon with weather and the internal combustion engine.

Yes, my truck slugs out on the triple "H" days, as does yours.
How to combat this? Install a turbo.

 

I am curious,, how many of you have the FIPK???alot of you have the K&N...Almost all of you are in the south(hot and Humid)..

The MAF tries to correct for this and does within its limited power,
this is where it is important to have a ramair/cold induction package...get air from the coolest place(in front of the grill)

The fuel we use is important, a compressor and dryer would work...

On the diesel, the problem is approached as way of an intercooler..This a thermal transfer device that creates cool dense air....this is another way to do it....

The way i approach the mod is try to keep the cooler dense outside air---in this state until the engine can benefit from it...
I thermo wrap the intake pieces to minimize temp loss by the underhood elevated temps...This is where the FIPK is going to lose...the aluminum tube is the biggest heat sink you could make, guess what goes through it????the alternative would be plastic(light colors work better)

I wrap everthing under the hood....air intake, A/c lines exhaust...
wrap it and insulate it...keep the temp and it will work more efficently(sp)...

want your A/C to work better--wrap it with insulation--you will tell the difference...wrap the exhaust to keep the underhood temps down...good luck...