He can't speed up e34 . what problem is it?

[baopa7]

This is my friend’s problem of e34.
When he starts e34 , Speed gives it so that engine braking suffers by all means if he speed up RPM stops, but speed was 20~30 km, and cannot go over 40km.... Thus He restarted again engin; if there will be it, is good.
Please help him…
-- my presumption is
1. poor distributing wires of mission
2. poor contact of selector
3. bad temperature sensor

[632 Regal]

what model E34? check the crank position sensor and the wires coming from it.