91 300 SL with 80,000 miles.

The car bogs as if it is starving for fuel or possibly air when the outside temperature is hot (>85). The problem has nothing to do with engine temp. I've replaced all normal tune-up parts, the fuel distributor, the voltage overload relay as well as the air temp sensor. The car has been serviced by 5 shops including dealerships in San Antonio and Austin.

Its been mentioned that a faulty control unit will malfunction when it gets hot.

Anyone have any ideas?

Thank you.