Tick-over too slow

My 1800 petrol is trying to tick-over at 500 rpm or slower, guess what - it keeps stalling.
I recently had the engine replaced with a "recon" unit and have been told by the garage who fitted it that the idle speed is automatically adjusted by the chip.
I am sure there must be a way of speeding up the idle to about 750 rpm - can anyone help?
Thanks,
Mike

It's more complex than a chip but half rite!!
All engine functions are controlled by the Engine Management System or EMS, sometimes it's called the Engine Control Unit or ECU.
Whatever is called it basically runs the engine. So idle speed, mixture and ignition is under computer control. There is no way of changing any operating function such idle speed without the use of specialist equipment. If this fault started after the new engine was fitted, it's likely something is amiss with either the engine or its fitting.

Hmmm, thought that might be the case. If you check out my previous thread regarding the replacement engine you'll see why I'm not that surprised.

Ho hum, there are times when I would rather not be proved right!