924Board.org

epsylon · Posted: Thu Apr 24, 2003 5:17 am Post subject: car runs bad over 3000 RPMs

i have run into two turbos with this problem. what would cause a 931 to loose power over 3000 RPMs. a dead turbo or is this a CIS problem.
_________________
'82 931
'78 928
Howell Henderson
South Padre Island

Alex Roy · Posted: Thu Apr 24, 2003 5:32 am Post subject:

either a CIS problem, or a vacuum problem. You should be able to hear the turbo whistle starting about 2000rpm, if you don't hear any whistling from the turbo, then you could say it was dead.

I had a problem on my 931 where it was like it was hitting a brick wall at 3000rpm, I unplugged the harness to the lambda control unit and it ran great......issue was the frequency valve had it's ground wire disconnected and it was messing up the fuel mixture when under boost.