A/C quits working when engine is under load.
When accelerating, my A/C stops blowing and only sometimes resumes blowing when a fairly low speed is attained. At highway speeds, it practically never runs. One mechanic said it was a vacuum problem and the dash board would have to be removed to fix it ($900). Is there an easier way to get access to the problem?
Thanks...that pretty much confirms my suspicions. I think it probably a fairly easy repair once you get to it, but the problem is getting to it.
There's a black plastic vacuum tube from the intake that runs along the top of the engine on the right side. There is a Check Valve a Tee, and a vacuum reservoir. One end of the tee goes to the reservoir and the other through a grommet through the firewall to your AC controls. The system is designed to hold vacuum whenever there is a high load demand (Climbing a hill, passing or taking off from a stop with a heavy load.) Check your tubing, check valve operation and the reservoir's ability to hold vacuum. $900? That's a lot of beer.
You can bypass everything in the dash and simply run the vacuum line directly from on top of the intake to the black vacuum line under the passenger side of dash. May have to drill a small hole to run it through but can be fixed this way for under $10 and will last forever.
My ‘04 E450 with the 6.8 gasser is doing this. It also happened with my ‘01 Ranger, so I know that the problem is a cracked vacuum line. Are there any schematic drawings that show the location of the vacuum line that is for the HVAC system? I’ve looked under the hood and the doghouse inside, but can’t seem to locate it. And, BTW, for such an important piece of the vehicle, why does Ford choose to go with such a lightweight, quickly deteriorating, vacuum line? Sure, it doesn’t have to be a stainless steel line, but anything that resembles a washer fluid hose is ridiculous! Thanks!
To all, the vacuum tank is at the very bottom of the outside system! The best thing to do is to relocate a new vacuum tank! At the inside on the right side push the grommet out, pull the black vacuum hose out from the top after hooking it with a flexible wire,or you can snake a wire up afterwards. You should find a T fitting at the end. Obtain a FORD check valve and make sure it is installed in the right direction! Hook the correct size hose to the offset inlet of the 90 fitting and run it to where you want the new vacuum ball
I have V10 Ford rv that stop blowing cold air from the ac going up good size hill ?
So, I’ve also had this problem in an E-450 can on my class C motor home. Took it to Ford. They wanted to replace the compressor, condenser, whole shooting match! For $1250! Be careful who you trust to diagnose this problem and be very careful about overspending to rectify this issue.
what did you do to cure the problem on the RV?
G A I have the same problem with my motor home as Guru79FY7. That is my V10 Ford rv that stop blowing cold air from the ac going up good size hill. This is a big problem when traveling in the summer months. The engine has lots of excess power and I want to eliminate the "Normal operation. When the load or the throttle position reaches a predetermined point the AC compressor will automatically shut off until the load or the throttle backs off then it will kick back in." Is there a way to easily do this?
https://youtu.be/XVlDr65GyZE
