Since there are no moving parts on a catalytic converter, you would expect that they would be fairly durable and long lasting and they are but, in spite of all of the advancements in catalytic converter technology, they still fail. Weatherford, Texas, we install replacement catalytic converter almost every day. Many times, catalytic converter failure is a symptom of an issue somewhere else in the vehicle.
It is imperative that you fix the problem that caused your OEM catalytic converter to fail because if you don’t, that same problem will likely destroy the replacement converter as well. The warranty that comes with a new replacement catalytic converter will not cover the type of damage listed below.
If your factory installed catalytic converter needs to be replaced, one of the problems below most likely contributed to its failure.
Engine Tune-Up Required
Engines in need of service and older engines that burn oil due to worn cylinder walls, stuck rings, and worn valve guides will produce by-products that can foul the converter. When an engine is operating outside of the proper specifications, wear and damage may be caused to the catalytic converter as well as the engine itself. Incorrect air/fuel mixture, incorrect timing, or misfiring spark plugs could lead to a catalytic converter failure or worse.
Bad Spark Plugs or Spark Plug Wires
Spark plugs that don’t fire or misfire forces unburned fuel into the exhaust system. Because the catalytic converter gets very hot, this unburned fuel can ignite inside the converter and could result in a partial or complete melt down of the ceramic catalyst.
Oil or Antifreeze Entering the Exhaust System.
When oil or antifreeze makes its way into your exhaust system creates a thick carbon and soot which coats and eventually clogs the air passages in the converter’s ceramic honeycomb catalyst. This causes two separate problems. First, these carbon deposits stop the catalytic converter from doing its job of removing harmful emission in the exhaust flow. Second, When the pores become clogged in the ceramic catalyst, exhaust flow is restricted which increases backpressure. This results in heat and exhaust backing up inside the engine. The excess back pressure created can actually cause internal engine damage. Your engine can actually pull burnt exhaust gasses back into the combustion chambers and reduce the efficiency of the next burn cycle and creating a loss of power and overheating of engine components. Worn out piston rings, failing gaskets, faulty valve seals or even warped engine components are all possible causes of this problem.
Unburned Fuel Entering the Exhaust System.
Ideally, the fuel that powers your vehicle is burnt up in the combustion chamber. Any fuel that gets through the combustion chamber unburned enters the exhaust system and can ignite once it reaches the catalytic converter. This can over-heat the converter far beyond its normal operating limit. and cause a Melt Down. Possible causes are an improper fuel mixture, incorrect timing, bad spark plugs, a malfunctioning oxygen sensor, sticking float, defective fuel injector or a faulty check valve.