Clutch Problems?

That sounds like a typical clutch slippage problem. On the 348, the clutch is on the back of the drivetrain package, so you don't have to remove the engine or the transmission in order to replace the clutch - it's quite easy. Just pull the rear bumper and the muffler(s) and the clutch comes right off.

You won't know how much work needs to be done until you actually remove and inspect the clutch. You could have a disc that is worn beyond the wear limits, and/or you could have a clutch that has become oil-soaked from leaking seals. Typically, you replace the disc and pressure plate. You could have either a single disc clutch or a dual disc clutch. You also have the option of having your old disc relined with new friction material, and having the pressure plate and/or flywheel surfaces machined to nice flat surfaces.

You DON'T want to keep driving the car indefinitely while the clutch is slipping, or you may end up needing a new flywheel, which will run you about $4000. You can check the Ricambi site for prices on new discs and pressure plate, but you have to know whether you have the single or dual disc setup (the dual setup is naturally more expensive, and is ordinarily found on the 1989-1990 models).

By the way, there is no adjustment on the clutch.

 

Here are some related clutch threads that I posted when my pressure plate failed.
It does seem like your clutch is slipping as Jeff has already mentioned.
Easy removal for inspection. I didnt remove my rear bar when I did my clutch.


http://www.ferrarichat.com/forum/showthread.php?t=86136&page=8

http://www.ferrarichat.com/forum/showthread.php?t=93933&page=11