magstar67

My 2006 F150 5.4 Lariat has the electronic HVAC control system and the AC doesnt seem to work right, I had my dealer check the charge last week and it was fine, when I start the truck up the AC doesnt cool at all, I know all cars do this to some degree but this is different, it puts out no cooling at all and doesnt get any better until you start driving then it seems to be fine for the most part.

Bought the truck over the winter so havent had it in full summer heat yet, so dont know how well it works in real heat and high humidity. The max has been about 85 degrees, but even at 75-80 it doesnt cool at startup until you start driving.

The truck has 105,000 miles.

What else should I have checked or any advice?

Thanks, Jeff

Chris_2005

Try adding a can of the R-134A to the coolant charge line. My truck did th same when I first got it. Wouldn't blow cold air til I drove. Added a can and it works great now. It's a good starting point and the cheaper fix of other possibilities. Hope it works.

techrep

iTrader: (1)

Just add the can of freon...don't check to see if it's over or under serviced...lol

bobkyle2

After you drive it.. for a few miles... And then stop... Does it keep cooling...

It it keeps cooling i would say your clutch fan is bad.. Mine did this.. And ford replaced the clutch on the cooling fan.. When you first start it and its hot outside.. It build heat instantly.. After you drive it a little hard for a few miles.. it starts cooling and stays cooling pretty well all day with no problems..

My truck has since started doing this again after about 50k miles.. So i think im going to just add a elec fan

Mod (Ret.)

At idle, there's not enough air flow through the condensor (mini looking radiator in front of the engine radiator) to remove the heat from the compressed freon (converts from a gas to a liquid, then back to a gas). Common problem with our trucks. When your cruising down the roads, plenty of air is flowing through the condensor, removing the heat from the freon, providing good cold air in the cab. AC works different then what some folks think; heat is removed from the air (providing cold air), rather than the air is cooled. Sounds bass akwards, but this is how it works.
When R134 was used in autos, the condensor had to be made bigger to help cool. This is due to R134 not being as efficiant as the old R12.

Whatever you do, don't attempt to just add more freon; too much will render your AC system inoperatable. What I did to correct this problem was to change over to an electric fan setup. I removed my clutch type engine fan, and installed an e-fan setup (Mark VIII two speed fan and DCController). A used Mark VIII fan from the bone yard is $50.00, a new one is $90.00, the DCController set me back about $100.00.

Now when I operate the AC, the fan kicks on to high speed and draws plenty of air through the condensor and radiator fan, and my AC is plenty cold at idle conditions. A pricy fix, but additional benifits are enjoyed with the E-fan setup as well.

Seminole39

Makes a lotta sense... right?

Mod (Ret.)

Nope. Not to me.

magstar67

Thanks guys I will check into electric fans.

Mod (Ret.)

Before you take that route, verify that your stock clutch is operating properly, and that your AC system is in good condition. There are other areas that can be faulty as well, such as a dryer, dirty or clogged condensor fins, etc.

Cmandes13

im having the exact same problem... BUCKO will it ever Just stop working? i have extended warenty on my truck you think a dealer fix would be coverd?