jerky idle after alternator replacement

[si03]

So I had my alternator and belt replaced last week and ever since then my idle has been extremely jerky. The mechanic had told me to drive around for about 30 mins and that would help to stabilize it.
Well that did not happen and it's still super jerky.
On idle it jerks from 2500 to 3000 and as soon as it hits 3000 the idle drops back down to 2500 and so forth. After cruising for about 20mins or so the idle stabilizes but it still keeps the revs solid at 2000 when at a red light or stopped.

Check engine light hasn't come on yet so I'm not sure what could be causing the idle to be so jerky and high.
Any tips or suggestions on what to look for would be helpful.

Thanks

[si03]

Any tips or thoughts would be helpfull.

[jwdep3]

Double check that you don't have a vacuum leak. If you don't have a leak, try cleaning out your iac. then, disconnect your battery for about 10-15 minutes and do the idle relearn procedure.

[si03]

Double check that you don't have a vacuum leak. If you don't have a leak, try cleaning out your iac. then, disconnect your battery for about 10-15 minutes and do the idle relearn procedure.

No vacuum leak but interested on the idle re learning procedure. I'll try this when I have some spare time. I'm now interested on cleaning out the IAC.