when my car is in drive its ok but when in park its idle to high what is the problem on 1991 Lexus LS400

and could that be the reason I failed HC emmision

by in Washington, DC on May 31, 2013
1 answer
ANSWER by , May 31, 2013
POSS VAC LEAK, HAVE CAR SMOKE TESTED TO CK FOR VAC LEAKS