98 EB xplr a/c cool at idle, warm to hot at high rpm

[AltairJr]

I have a 98 Eddie Bauer Explorer with the automatic climate control. I have just serviced my a/c: vacuum, check for leaks, refill, the basic stuff.

When I turn on the a/c, my condenser sweats and gets nice and cold, but only a portion of that makes it into the cab and only at idle. When I increase my rpms (doesn't matter if I'm parked or going 70) it gets warmer until it's uncomfortably hot, but will cool off as soon as my rpms are low again.

I think I may have a vacuum leak somewhere but I have no idea how it might affect my problem.

 

[TOMANDPAT]

Yep, sounds like a vacuum leak. The first place I'd check would be the vacuum reservoir tucked up inside the inner fender on the passenger side, and the small vacuum lines going to and from that reservoir.

Tom

 

[AltairJr]

Alright I'll check that out. I should also mention that when I have the glove box out and I stick my hand behind the actuator I can feel nice cold air circulating but it never makes it to the registers, and even when I rev the engine and warm air comes out, it's still cold right there by the blend door. Is the blend door in an eatc system vac controlled, or what? I don't quite understand how a vacuum leak would cause my problem, even tho I've diagnosed it that far on my own.

 

[AltairJr]

so I finally had a little free time (and I do mean a little) to see if I can check on the vacuum reservoir lines. Do I need to take off the inner fender to get at it or can I get at it from underneath.

I ask because I can see where the lines go, I just can't see or get to where they finish.

And if I have to take off the fender, is it as straight forward as it looks or are there a bunch hidden screws/clips I gotta look out for.

Thanks for everyone's help.

 

[AltairJr]

Yup, I had a decent size hole in the hose going to the reservoir. For the time being I just put duct tape on it. Now I actually get cold air when I'm idling, but it warms up under load like usual, but not as hot. Either duct tape wasn't sufficient or I have another leaky hose.