When changing the air filter, it is easy to knock off a hose on the air filter housing, which is part of the emission control system. If the vehicle is driven with this hose disconnected, the Check Engine Light will illuminate.
Car Problem Reports
Toyota Highlander Check Engine Light Due to Hose Off of Air Filter Housing
Toyota Highlander Problem
Engines Affected: 2.4L 4 Cylinder, 3.0L V6
Average Mileage: 105,765 mi (81,000 mi - 140,795 mi)
Visitor, 2003 Toyota Highlander, 3.0L V6, 140,795 mi
Check engine light & VSC light come on together every time my air filter is changed. Hose comes off. Put hose on and disconnect battery to get the check engine lights to go off.
oil change place knocked hose off air filter housing...check engine light went off a few weeks after I fixed it.