Why do catalytic converters fail? There are numerous reasons, one of them may be because of the fouled plugs that can cause unburned fuel to overheat the converter and melt the catalyst to a solid mass. When the oxygen sensor is not functioning properly, it can cause an excessively rich or excessively lean condition. If the mixture is too rich, the catalyst can melt down. If the mixture is too lean, the catalytic converter is unable to convert the hydrocarbons into safe elements.

Oil or antifreeze entering the exhaust system can block the air passages by creating heavy carbon soot that coats the catalyst. The carbon deposits can prevent the catalytic converter from reducing harmful emission in the exhaust flow. Also, the carbon deposits can clog the pores in the ceramic catalyst and block exhaust flow, increasing backpressure and causing heat and exhaust to back up into the engine compartment. Your engine may actually draw burnt exhaust gasses back into the combustion chamber and dilute the efficiency of the next burn cycle. The result is a loss of power and overheated engine components.

Catalytic converters can also have some physical damages The is a dense insulating mat protecting the catalyst inside the catalytic converter. His mat can break when the support hangers get broken. Rocks or other road debris can also hit the converter, causing the internal mat to break also. Off road vehicles often suffer this type of converter failure. Once this mat starts to break up, it will collect in the smaller passages and clog the converter.

Another safety reminder for all motorists is to never park your car over tall grass or piles of dry leaves. Your cars perfectly running catalytic converter gets very hot and is enough to start fires.

This entry was posted on Thursday, July 26th, 2007 at 4:45 am and is filed under Maintenance. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.