My 760 Turbo has suddenly experienced a power loss on high speed. She's running fine on low speed while no turbo push applied. Driving on a highway is difficult, she tends to slow down while I'm applying more gas and turbo push to her. Her indications are as follows: rev'ing high, turbo gauge needle pointing to approx. 1 o'clock position (varies with gas applied) and speed slows down as applied more gas. I've checked all vacuum hoses and turbo ducts/air hoses for leaks but nothing found. I even checked the inner part of the turbo assembly for foreign objects and the fan by turning it by hand which checked ok. Do I have a faulty turbo or something else. Any advise guys?

Are you seeing any smoke from the tailpipe when you hit the turbo? I had a similar problem with my 89 740T. After a lot of investigation, it turned out my Mass Air Meter was bad. Got my hands on one from a freshly wrecked car and problem solved. The car was running way too rich. Take it out on the highway and punch it....look in the rear view for smoke. Mine started slowly but after a few days I was belching black smoke. I could be way off but its worth a look. MAMs are not cheap but if you can get your hands on a known working one from a friend for example, they are easy to put in. It might be worth a shot to just try that before you buy one. Good luck.

I took the AMM out and cleaned it with carburator cleaner, but no cigar... Unfornately, I don't know anybody that willing to lend their AMM for my troubleshooting efforts. I'm not getting black smoke from the tailpipe when I speed up. I can only speed up to 55 MPH max, and when I try to get turbo boost, it seems like it's choking everytime turbo gauge needle reaches the yellow scale. I'm contemplating to take my brick to the dealer if can't make any headway soon. Thanks for responding.