I feel intoxicated when driving (esspecially in the summer, with windows open), it's most noticeable when driving above 3,000 rpm. It smells and is intoxicating. I recently dismissed it as being from exhaust and thought it might be an oil leak leaking on hot engine and/or exhaust parts. When I'm stopped I can see how the intoxicating fumes get in my car, but when going above 140 km/h on highway how can the smell from the catalayic converter get in the car? I'm missing one of two catalayic converters. Could the smell at high speeds be caused by missing cat. converter? It only really smells when going fast with windows open.