Help! Headlight/alternator Surging

[ahlenius 0]

My Smart recently Starting surging i think its the Alternator. the head lights ars surging and so is the engine at a about a 40hz freq. i have no warning lights but the dash display surges to. any had this happen 43000km cdi cabrolet in Tx ...i am thinking im going to have to replace an alternator. Anyone?

[MikeT 744]

The engine is surging too? Air leak or cracked exhaust manifild..... The voltage regulator may be shot too.