Nutter

I have a few questions about some quirks I have on this car..

when I want heat specificly defrost on the front windshield, my ac light comes on and my pump seems to run while on this setting as well.. is this normal? I have looked in my haynes book to no avial, also i came into the chevy dealer here in town and they are at a loss as well... instead I was referred to another company that rehabs older cars, also told they where unsure...
now the ac works great, it can make ice on my windshield if I go for a long drive. It can get pretty darn cold!
so i am seeking advice on why my ac pump comes on during heat, on defrost setting. pushing my ac button does nothing in this setting....can i just unhook the pump while I drive the cold months? the ac pump makes the cars rpm surge when this is happening...
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This one is weird, I got the car like this about 5 months ago... it seems fine but I dont like something directly hooked to the fuse box "not fused".
my coil pack is wired directly into the under hood fuse box, with an in line fuse.. Is my coil pack techniclly on all the time?
I did do some research on this... but I am at a loss still...
The wire that come through the harness is dead. I suspect corrosion somewhere!
where can I hook my coils up to that will not harm them, but also in a neat fashion?
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This is a weird one too..
I have an exhaust leak at the manifold pipe where the exhaust pipe meet. I have replaced two donut gaskets so far.. This also gives my car an check engine error light. code isnt important as i know what the underline problem is. And i have replaced this sensor as well...
So there is this piece of flex pipe the supposed to be under the motor on the exhaust pipe.. Instead i have a strait piece of pipe welded in place of that. so in turn it makes my gasket prematurely wear out very fast.. What can i do instead of buying a whole new exhaust system?


Thank you for your time!