'87 N/A, on start-up it shoots to 3,000 for 10 seconds, then drops to 1,500, and then it'll pip back up to 1750 and just sit there.

The engine also has an odd thing as after it's being revved, the engine will hesistate and then go back down to idling at 1,500.

From the shop manuals and a few local opinions, it sounds like something with the BAC... but I wanted to get some ideas of what it could be.

 

dont touch the BACV yet. First make sure there is nothing getting stuck open on the throttle linkages, like the MOP rod for instance. Second, check to see if your TPS is set, than do a vacuum test. If you have good vacuum and your TPS is set, proceed to adjust the idle speed with the screw on top of the TB. If that doesnt do it, you might need to adjust the plates themselves.

But make sure there is no vacuum leak.

 

Thanks for the tip, any other suggestions out there?

 

Does the car eventually begin idling properly after its warmed up? I would DEFINATELY try setting your TPS first.