Well, no expert here. . . .
because I've never had a problem with the A/C (tnx God!).
But does sound like a temp sensor problem. In my car, there's a differential temp that when you rotate the wheel(s) to a colder temp that exceeds this inside temp differential, the blower then picks up the fan speed.
So in your example, of 98F outside, I would think that setting the temp wheels lower than 70F or so, should send the blower into high(er) speed operation.
Need a pro hear that knows for sure but you can list the code(s) from the A/C diag readout for info.
Regards . . . . JimF
'94 S500 Cpe
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