power over 2000rpm

[m.s at biosys.net]

There is a rectangular connector that plugs into the wiring harness.
This sits on top of the engine( right of midline) and connects ( i
think) to the MAF. If this is loose it will cause exactly the
symptoms you describe. i duct taped mine and it fixed the problem. i
don't have the car here to look and give clearer info and it has been
6 years since i solved the problem but i suspect this is your
problem.

HTH
derek