Questions about idle on my 348

Not a cause for concern.

Could be:
1. throttle body air bypasses are a bit clogged and need opening or cleaning
2. bad gas (use Techron!)
3. sensor needs cleaning or replacing (e.g. MAFs, coolant temp, O2's)
4. sticking throttle cable that needs cleaning
5. clogged fuel filter, air filter, or exhaust/cats
6. sticking fuel injector that needs cleaning
7. low coolant or engine oil (or overfull engine oil)

 

You forgot #8 Shemp

If the battery has been disconnected you will need to let it go through relearning the warm up parameters.

 

Saved that one just for you! Nyuk, nyuk, nyuk!

 

My comments:
1. Not likely since these would have given you an indication before if they were starting to foul. Also, you'd have to have taken in a lot of junk in the intake to clog these guys, given their location, so something else would have probably fouled earlier. They also don't fall out of adjustment, but someone could have turned the screws accidently or on purpose (neferious mechanics).
2. Yep, my No. 1 guess if the car has been sitting awhile. Top off the tank with new fuel, drop in some Techron and modulate the "go" pedal. This would also work for No. 6. You might be able to drop in some octane boost instead to "refreshen" the lost octane from older fuel, but be carerful what you add since much of these products are crap.
3. MAFs should probably be checked to proper resistence (383 Ohms), but I think that a faulty sensor woiuld have shown up earlier in some way.
4. This one I can't see. However, when the stooges were over to replace my plenum, goth purposely reminded us to keep the throttle cable loose becaus eif it was too tight, the engine might idle high. Well, we did and the damned thing came off eventually (in the garage thankfully). (Didn't mention that to you guys, heh heh). My car had similar symptoms as yours so who knows?!
5. Unless you drove through a sandstorm recenetly, not likely for a car that has been sitting in the garage. You would have seen symptoms earlier.
6. Yep, another good suggestion and already addressed.
7. Maybe and I have no personal knowledge of how this happens, so I defer to Shemp and the stooges.

Curly Joe - Nyah, nyah nyah, woob woob woob woob, gruff, gruff...

 

Probably just needs an "Italian" tune-up...

 

Colin, this is a huge concern and I think you should sell it immediately, to me of course. It could cost you thousands to fix this serious problem, so selling it is your only remedy.