1993 Mitsubishi Eclipse 4 cyl Two Wheel Drive Manual 124000 miles
I'm trying to locate the cause of a fume leak in the car cabin that causes slight lightheadedness, which was present before recent repairs. The catalytic converter has been replaced very recently. And the car was also very recently tuned with new spark plugs, wires, air filter, fuel filter, IAC motor and oxygen sensor. I've tested the cabin with an inexpensive CO indicator used for homes (during long drives) and don't get an emergency beep or indication of dangerous levels of CO.
The first thing to check is that the exhaust system is complete free from any leaks and the tail pipe is extended beyond the rear of the car, usual places that can cause fumes to enter the cabin, (the pressure is usually a little lower than the out side of the car when driving so any fumes will be drawn into the car) are faulty boot seals. If the exhaust is sealed with no leaks this should not be the problem as it sis fumes trapped under the body that are are at rick from being draw in. I would also check the fuel system for any minor leaks, and have the A/C & heater vents treated for mold & mildew as this can often be a hidden problem as well. Start here.