1998 Corvette C5, the blower for the AC / vent / heat does not have a lot of output into the cockpit? When on AC it does but cool off as it should even on the highest fan setting.
The blowers in most cars have a blower regulator that determines how much current is given to the blower based on what selection you make from a knob etc. See if you can research the blower regulator. That is normally the problem instead of the blower itself if it is work on on one speed and not the others.
Hate to ask but where is the "blower regulator" located?
They vary in location. Some are behind or near the back of the glove box, others are behind the big fuse boxes under the hood near the firewall. Its best to ask the dealer if they have a location of it or hope you get lucky and find a Youtube video of where it is. Most likely one of those two places is where you have the best chance of finding it. Search Youtube for a 1993 Buick Lesabre blower motor regulator to see the one I posted that one was behind the big fuse boxes on the outside of the firewall and a real puzzle.
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