The Air Conditioner on my 03 6.0 F250 works great!! EXCEPT when I put the engine under a load. Yesterday, I was pulling a trailer max speed of 40 MPH, with the transmission in tow mode. The air conditioner would not work at all. Today, no load, air conditioner has no problem.

Any ideas?? as you can imagine Air Conditioning in Tampa is "must have"

 

check the belt, tensioner and fan clutch.

 

Ok,, belt was replaced about 25K miles ago, not an easy job. I am not sure how to check the tensioner,, but it looks ok. As far as the fan clutch,, I hear it engage and disengage so it appears to be working.

I thought about a temp issue, so I checked the EOT and ECT while under load. I was surprised that they were real good,,, 197 ECT, 203 EOT,, per scan guage. Outside temp was 92.

 

Any loss of coolant?

 

wat about the vacuum pump? would tat be a problem, guys?

also, wat about the reservoir next to the vacuum pump? tats hvac-related. also, if ur vehicle has climate control, then i'd pay attention to the vacuum lines too. could have been chafed or accidentally unplugged.

sorry guys, jus covering all the bases. or maybe i might be barking up the wrong tree.

 

Any loss of coolant?? that is an interesting question.

I am losing coolant, about two or three drops per night. less than one teaspoon a night, all on the passenger side. I think it may be a heater hose issue,, I just havent been able to really see where its leaking.

But in 4 months of watching this, i have yet to add any coolant to the system.

 

interesting. wow.

 

check the heater controll valve to see if its leaking. its either that or the egr cooler to oil cooler hose.
if its the controll valve you can get just the vale its listed in the 05 excersion catalog.

 

Ok, I am trouble shooting the leak,,, I layed paper towels under the valve, and the " T" that goes to my coolant filter,, . We will see if I find the leak. Do you think this really small leak can cause the A/C issues??

 

Not really - I think they are separate issues. I was actually wondering about a small head gasket issue (you can vapor lock the coolant system).