Replaced the timeing chain and the tentioner few weeks ago (at the shop). First couple of days the car seemed to almost stall right after start. Revs would start at 1000 and than drop below 500, than pick up again. But few days later the situation had changed. Now they start at 1000 and than slowly go up, sometimes almost to 2000 rpms. Car revs high and when in gear but at a stop, the econo gouge showing more than a quarter of scale up from minimum. Is this timing or something else ? What should I do?

HMMM.
This could be a problem with a vacuum leak or a problem with timing. I think the shop should look this one back over.