Hi Dave,
Check the breather tube that goes to camcover not unusal to find them split. Sounds like air leak, or poss idle not set correctly.
With her running spray some WD 40 around the manifold, carbs ect. If the engine speeds up due to 'sucking' in the WD40 theres your leak and where it is, SIMPLES ! !
Cheers John
LIVE LIFE A QUARTER OF A MILE AT A TIME!
1979 3.5 FHC(STATUS PENDING!!)
1982 2.0 DHC NOW A 4.6,ON THE ROAD NOW KICKING AR5E !!!!