Clogged catalytic converters can reduce the exhaust flow from your engine and, therefore, reduce the car performance. The reason catalytic converters become clogged is because the engine does not burn all of the fuel in its cylinders, and instead releases that fuel down the exhaust and then into the catalytic converter, which is filled with a foam that is very spongy.

Symptoms

If your catalytic converter becomes clogged, the "Check engine" light will turn on. Other symptoms include a very weak feeling to the car's performance when accelerating. There might also be a different sound to the exhaust, and exhaust emissions will increase, as well.

Using a Scanner to Check the Catalytic Converter

If you have a scanner, you can hook it up to the port that is under the dashboard on the driver's side of the car and click "Read." Look at the code your scanner shows you and check it with the code sheet provided with the scanner. If the scanner shows you that the problem is associated with the catalytic converter, it is very likely that it is clogged.

Checking Temperatures on the Catalytic Converter

This is the easiest way to check for a clogged catalytic converter: Use your hand to feel the temperature of the catalytic converter. If the temperature is much hotter at the front than at the back, you have a serious clog. However, this test is only good to a certain degree; your exhaust may be lightly clogged and only show a very slight temperature difference, which will not be accurately detected by the hand. Note: Do not touch the catalytic converter immediately after the car has bee running--it gets very hot and it will burn your skin. Give it enough time to cool off to a certain degree before checking temperature by hand. Instead, you can use a laser thermometer, for a safer temperature check.

Source:

Scotty Kilmer

AA1car.com

Autoshop101.com