Pontiac Repair: 1988 MAS sensor, maf sensor, pontiac service

Question
1988 Pontiac Formula 350. The original Bosch MAS sensor blew and aftermarket refurbished units and new AC Delco MAS is still causing occasional rough idle and misfire at highway speed. Local Pontiac Service Manager told me anything other than an original GM replacement unit won't work.
Disconnecting MAS will cause the car to run fine, though service engine light comes on.
Any suggestions?

Answer
Hi Andy:

I agree with him. Anything othere than original equipment emission sensors are JUNK. use only origianl equipment parts.. If memory serves me right I belive there is a relay that runs that sensor on that car??? Youm may want to look into replaying that as well. My online service manulas only go back to 1998 so I can't tell you for sure But I want to say there is one for that I may have been called a Burn off relay??? but back to your original question stick with a genuine GM "bosch" MAF sensor. Good luck :)