A/C won't work when accelerating

[falcaraz]

For a while now I've noticed that whenever I have to accelerate my A/C stops blowing cold air until the engine has slowed down a bit. It's as if it will not work when there is a load on the engine.

Is this normal behavior for my truck?

 

[waskly]

only when you on the gas do you lose ac?

if so check the check valve.

 

[albi1cnobi1]

Check to see if the cold air is coming out of the defrost vents when that happens. If so you have a vacuum leak in the controls somewhere.

 

[falcaraz]

only when you on the gas do you lose ac?

if so check the check valve.

Check to see if the cold air is coming out of the defrost vents when that happens. If so you have a vacuum leak in the controls somewhere.

Also a few months back I noticed that the temp control stopped working for a day. It was stuck on hot until I moved it back and forth between hot and cold til it worked again.

Does this mean a definite vacuum leak?

Also where would be the best place to look for the leak?

Thanks in advance.

 

[falcaraz]

Just did a quick test and when the A/C stops blowing through the front vents, it keeps blowing through the defrost.

 

[albi1cnobi1]

You've got a vacuum issue. Common problem, check the lines in the engine bay. Passenger side close to the inner wheel well, and check the vacuum globe as well. It's inside the passenger side fender below the air filter.

 

[Joe Heenan]

For a while now I've noticed that whenever I have to accelerate my A/C stops blowing cold air until the engine has slowed down a bit. It's as if it will not work when there is a load on the engine.

Is this normal behavior for my truck?

 

[SoHK_alumni]

Good chance the vacuum check valve in the vacuum reservoir has failed.

Replace the reservoir or add a check valve between the engine and reservoir.

 

[Spuddy]

Hmmm... sounds familiar... especially uphill.

Geez, I thought these were supposed to do that.

Next project!