Climbing Idle Speed As Engine Warms Up

[knipdlo]

Hi I'm a new owner of a 1983 Targa SC, the car runs very well but was parked for a while before the owner passed. The car starts right up very well, but stays at a slightly high idle. As the car begins to warm up the idle climbs higher and higher. The tach does not currently work, so I'm not sure where it climbs to- but I usually shut it off around what sounds like 2500-3000 RPM after about 2 minutes. It is very complete and totally original. The only thing I can find so far is the decel valve or aux air valve on the passenger side has the vacuum line disconnected. I'm not sure where to go from here? What can I test to figure this out?

Thanks

[offroader1006]

Check your distributor to see if the advance weights are sticking.

Checking your vacuum is always a good idea.

[stevepatfred]

I has a similar problem that turned out to be the vacuum advance on the distributor.