Bad Throttle Position Switch, what symptoms?

[Magnus_944]

I checked my thr. pos. switch today and found out that it does not work properly referring to the haynes manual. I don't get zero ohms on on the "idle terminal" as I should when the throttle is closed. Can this be the cause to that my car is running bad at low load and below 3000 rpm? When I'm cruising on the freeway at 50-90 kmh the car is jerking and running bad, but if I step on it it runs fine. I have an 944na -83 euro (living in sweden).
All answers are appreciated.

/Magnus