Two problems related to engine exhaust system have been reported for the 2003 Toyota Matrix. The most recently reported issues are listed below.
My check engine light came on, and the local Toyota dealership charged me about $50 to tell me my catalytic converter needed replacement at a cost of over $1,000 for my 2003 Matrix with about 92,000 miles. Seemed unlikely, so I took it to a local non-Toyota repair shop, his computer also showed catalytic converter, but he said the way the car was performing, it might be the oxygen sensors. He replaced both, and the car has been great ever since. Too bad my local Toyota dealer wanted to gauge me.
A strong chemical fume entered through the passenger compartment of the vehicle.