our van has just started missing @ idlesometimes dieing out. changed the plugs on 2004 Nissan Quest

then got a code to change the o2 sensor. still misses @ idle... pulled a code for maf sensor, changed that. still misses.. now a multi plug misfire... What other possible things can I change????took it to the dealer, After 100.00 bill for diag. they say it needs serp. belt cracked, valve covers seeping, and motor mounts broke... WHAT the hell does that have to do with the misfire at idle.... it runs great @ operating speeds. HELP....

by in Jacksonville, FL on April 19, 2012
2 answers
ANSWER by on April 19, 2012
Not much if any...I cannot tell you whats wrong. Suggest to get a recommendation for a good shop in your area. Friends or coworkers may know someone.
ANSWER by on April 19, 2012
SOUNDS LIKE YOU MAY HAVE AN ELECTRICAL ISSUE WITH COILS BREAKING DOWN, SEEK ANOTHER EST