Four problems related to manifold/header/muffler/tail pipe have been reported for the 2001 Honda Civic. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 Honda Civic based on all problems reported for the 2001 Civic.
The exhaust manifold is cracked, causing dangerous fumes to enter the cabin of the car. The fumes are most noticeable when driving at low speeds, and they are enough to cause a strong headache/light-headedness which could potentially cause an accident. There are hundreds of complaints filed on the internet for this exact model/year Honda.
The contact owns a 2001 Honda Civic. The contact stated there was a crack in the exhausted manifold and smelled gasoline. The contact took the vehicle to the dealer and was told there was a fuel leak. The vehicle was not repaired. The failure mileage was 99,000 and the current mileage was 99,200.
I had an exhaust leak in the engine compartment at 85,000 miles. I removed heat shield and saw the exhaust manifold cracked around circumference of pipe. This is where the header pipe is factory welded to the flat mounting plate. Exhaust manifold is part of catalytic converter. Warranty expires at 80,000 miles. I'm stuck with this defective part. Taking part to a professional welder to try to repair it. Otherwise, I'll have to spend $700 to $1000 to purchase a new one from Honda.
When driving under wet road conditions muffler vibrates. Cause unknown. Please provide any further information.