A/C Works...for a bit

Been reading some other postings but could not find an exact error like the one that I have. I know that A/C systems are tough to figure out on the net, but this is what I have. There might be a leak in my system, but no tech can seem to find it. A dye was used with no luck. I have to refill my system every so often. When I stomp on the gas, my fan goes from vents to defrost and when I let off the gas, it goes back to vents. I never see condensation dripping from my A/C and think it might be a evaporator. Any thoughts other than don't stomp on the gas and "that sucks".... :eyes: ?

The change from dash to defroster upon heavy throttle is a pretty good sign of a vacuum leak. There's a blimp-shaped vacuum canister inside the front bumper (at least, that's were it is on 4.0-equipped rigs) that's made of plastic - checking that, the lines connected to it, and looking for any hoses with dangling ends would be a good start.

For the lack of dripping, there's a drain line from the evaporator that is supposed to allow condensation from the A/C system to escape from the vehicle. If you don't seen any drips even when the A/C blows cold, your drain is probably clogged, and should be cleared before the area that the drain services overflows and gets your interior wet.

What year/engine do you have?

Rob

Funny you should mention the vacuum bottle....I did have a cut line going to it and replace the damage part with a "fuel line" type of piping. I guess it did not seal like it should even though it was a tight fit.

I have a 98 4.0L.