engine issue

Hi all, my 1995 K11 1.0 65,000 miles has over the last two years developed a problem that is slowly getting worse.
For some reason you notice it most in third gear, when accelerating up a not too steep hill the car seems to misfire though never backfire.
The car will judder.
When its really bad changing down a gear sorts it out otherwise backing off the throttle helps, don't know if there's a connection but I have noticed when manouvering the car with engine hot the tickover can stay higher than normal for a few seconds.
Any thoughts appreciated.
It is definitely an engine issue, I have tried changing the throttle position sensor and this made it worse, until I got it set in the correct position.
I keep thinking it might be the throttle body issue with dry solder joints, but the car uses no extra fuel which some say is a sign of that fault.

Does the shudder appear to be coming from one of the front wheels? It could be a drive shaft (CV) issue. If so, don't leave it too long, or you'll need a tow. Get to a mechanic soon.

cheers,
Greg