Buick Skylark heater issues

TOMCAT1078

MEMBER
1996 BUICK SKYLARK
6 CYL
FWD
AUTOMATIC
120,000 MILES

1996 Buick Skylark heater only blows warm when driving on hwy. It starts blowing cool air when idling or driving at slower speeds. What could be the issue?

Tuesday, January 11th, 2011 AT 7:46 PM

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Make sure the coolant is full. With the engine hot, running, heater on high, feel both heater core hoses. Both should be hot. If they are not both hot, there is a restriction in the heater core. If they are both hot, have the blend air door checked.