I've just aquired this '96 SSE Supercharged.... what a beast she is! Anyway... The air conditioning is weak.... luke warm and the fan doesn't seem to blow very hard. The threads I've found suggested cleaning the evap box. Sounded reasonable, so I pulled the relay cover to take a look and that'* when I saw cracks in the large plastic box directly below the relays. (I have pics, but no Idea how to show them here)...
I reached in and touched the box and a large piece instantly broke off... turns out it has the consistency of a hersey bar... the entire area seems to be about the same.... I'm referring to the large black plastic box/area just left of the fan at the firewall. I now have a baseball sized hole in the plastic, leaving the yellow layer beneath (some kind of insulation) visable. All this leads to my questions:
1: Is this the evap box that I should be trying to clean?
B: Would large cracks in the box ( and now a hole) cause the weak airflow through my system that I've seen..... It'* only been pushing about half the volume of air you might expect from an average AC vent.....
And First Of All..... Assuming that the hershey bar box thingy is the evap box aforementioned, and I need to replace it (due to it'* Hershey Bar-yness)... how hard is it to swap it out and where would I get one?

ALSO...... when the car is running and driving, I hear a very high pitched whine. Not loud... not obtrusive. But there nonetheless. Sounds like it'* more from the engine than the tranny.... but I haven't checked it yet to be sure. Any thoughts on that disturbing little sound?

Thanks!
Mike

Hi Mike, Welcome to Bonneville Club!

The heater/ventilator/air conditioner (HVAC) ductwork you are referring to holds the blower motor and protrudes into the engine compartment through the firewall. It is a stamped metal duct system that brings fresh, outside air in to the cabin from under the cowel or ducts air from the cabin to the blower motor (which you will see sticking out of the ductwork with its own plastic cover). The blower motor then pushes the air through the duct to the evaporator and depending on how your airmix door is set, through the heater core and then into the ducts that run to the floor, dash, and windshield. In some of the higher-end cars, the engine side of the HVAC duct is covered with sound deadening and heat insulating materials comprising fiberglas over the metal and a thick plastic cover over the fiberglas. The thick plastic gets very brittle over the years and can easily break. That is what you are describing as Hershey-bar material, I'm thinking.

Check Techinfo for the method for cleaning the evaporator core- you will have to go a little deeper into the ductwork to find it.

Mike, that whine could be the supercharger winding up. Does it coincide with the demand for immediate power? Oh yeah, Welcome to BC, you've come to the right place my friend.

I belive the whine is constant..... and it'* low enough in volume that you don't necessarily hear it while driving.... I'm be going out this afternoon, and will play closer attention to it and post what I hear later on....

Any idea on where could order a replacement noise panel cover thingy... that plastic part that is breaking up which I described the first post? I'll be digging into the unit to clean the evap in the next week or so and would like to replace it so I don't have a big ugly hole in my firewall!

Thanks for the words of welcome! These forums are just about the best result of the existence of the internet! We have an old Jag we're working on as well, and I can tell you I'd be lost on that thing if not for Jaglovers.com! (The Bonnie runs stronger, by the way... but don't tell my Jag I said that. They're very tempermental, you know!)

--Mike

Oh yeah! How do I post pictures of the car / problems from my hard drive to this board?

Could the whine possibly be the blower motor itself? Try disconnecting it and see if it goes away.

You may be able to find your part at a junkyard, or perhaps one of our members has one that could be sent to you.

As for pictures, set up a free photobucket account.

www.photobucket.com

I replaced the duct cover on my '95 with one from a junkyard, but I could not find a good cover for the blower motor, so I bought that from a dealer, iirc, it was about $10. However, I did the cover swap with the engine out of the car. I really can't imagine doing much more than the blower cover with the engine in place. You may be able to cut just the missing piece out of a junkyard cover and piece it into your old one.

When you go to the junkyard, you will see a lot of cars that do not have the cover or insulation, just painted metal. That suggests that there will be no adverse affects (other than perhaps more noise and slightly reduced cooling potential), from a damaged or missing cover. So, it'* not something to get really too concerned about, even though it looks really bad. Well, I suppose if those pieces fell onto the hot exhaust manifold, they could start a fire. Which reminds me, there should be an aluminum heat shield between the duct cover and the exhaust. Make sure that is in place.

Just some thoughts.

Okay... I drove the car and listened to the whine... definately follows the rpms... ie higher pitch and louder as I accelerate... drops back with the trans shift and increases again with accel.... etc... it is constant, other than at idle. With tranny in park, I rev the engine and can hear the whine at that time......

Any thoughts on that appreciated. I've also got a new issue, but I'll start a new thread for that one.... so if you know anything about the alarm system on this car, see that thread.
--Mike

Still sounds like the Superharger to me. It'* a nice sound, dont worry

Do you only hear the whine at WOT or hard acceleration?. It sounds to me like a power steering pump, the pumps tend to whine sometimes.

I hadn't thought about the power steering pump.... mainly because it doesn't increase in volume when turning the wheel like my old Towncar does when it runs low.... I'll check that one tomorrow......

thanks!
Mike