help with multiple issues

I have a 1998 4 door tahoe LT. i actually love it even though it has been drainingg me for some time. I need to replace the weather striiping in the rear passenger window any ideas. also a couple of problems with my heater/ac it blows hot 80% of the time however it will start blowing cold for no reason and it will stay cold when stoped then heat up agaian with movement to the gas pedal. i see most believe that this may be the gasket however wouldn't I see a leak on my driveway and wouldn't it blow cold continuously also my heat ac only works and one setting if you try to change the vent settings by dial it will take at least 20minutes for it to kick over ie.. from defrost to floor . I would appreciate any input. w e have chnaged the fuel pump transmission oxygen sensors cv joints. too much in to give up. and if anyone knows a link to actually fix the gaskets lets me know. thanks for your time

Check the antifreeze levels for heat issue, also check the under dash connections for the heat to be diverted from defrost to floor or vents.

thanks for the reply

Heater Problems too!

Did you find out the problem? Mine is acting up too!:nonod:

OK I would say a heater core or low coolant is causeing your no heat problems. Now for the door not changing modes when switched to vent or defrost. In older GMs the seal they used to seal the doors that moved after afew years would almost turn into a tart like substance that makes the door stick. But that was in the late 80 to early 90, never really heard of it for newer vehicles. If it isn't that could be wiring or a bad motor that turns the door. It is all electronic now a days

When's the last time you flushed your radiator? Mixing DexCool (Orange) and standard (Yellow/Green) anti-freeze will turn the coolant into a gel. This will clog your heater core.

Flush your coolant. Change your thermostat (if it pops early, then it will not allow the heat to build up.) Refill your anti-freeze with 50/50 and check it again. If you already have gel, then from what I understand you'll have to change out your heater core.

Hardwarz