The thread on white clouds prompted this for the record.

Black Smoke - overly rich fuel mixture - fuel control problem. Check
fuel and induction components.

White Smoke - usually coolant related - gotta leak somewhere into the
Exhaust system - Could be head gaskets, cracked heads.

Blue or Blue-white Smoke -  Usually an oil problem - rings, bad valve
guides, scored cylinder wall. A compression check is in order on this
one. Often the tailpipe pipe will be oily.

Regards,

John Rodgers
88 GL Driver