How to Tell If Catalytic Converter Is Clogged?
- 1). Drive your vehicle to test performance and engine operations. A vehicle with a clogged catalytic converter will exhibit excessive exhaust back-pressure. Testing for this is not difficult. Listen to your engine when accelerating. If the engine sputters, hesitates or experiences unequal power delivery, you have a problem. It may not be the catalytic converter, but once you have symptoms you can narrow the possibilities down.
- 2). Hook your vehicle's diagnostic connection (usually underneath the steering wheel, near the pedals) to an OBD-II scanner. Scanners can be purchased for as little as $80 and will work on all vehicles 1996 and newer. If you cannot acquire a scanner, take the vehicle to your local auto parts store. Many auto parts stores will hook a scanner to your diagnostic connection free of charge; they'll even let you write down the trouble code.
- 3). Analyze the trouble code coming from your vehicle. A clogged catalytic converter will always result in an OBD-II trouble code because the catalytic converter's function is so important to meet emission standards that the diagnostic system has a separate monitor for catalytic converter efficiency. Look for a trouble code ranging anywhere between P0420 to P0439, which would indicate catalytic converter trouble.
- 4). Replace your catalytic converter if it is clogged or faulty for some other reason. A clogged catalytic converter could cause extreme engine stalling if exhaust back-pressure gets too high. This could leave you stranded on the side of the road, or even in an accident if your engine stalls in heavy traffic.
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