Catalytic Converter Diagnosis 9 Easy Methods for Pro Results

Higher mileage vehicles can developed a plugged or inefficient catalytic converter. This video shows using simple steps to troubleshoot and fix the issue. This video discusses 9 methods to test and prove that the catalytic converter is faulty. It is often best to try multiple methods to be sure of a cat failure due to high cost of replacement. Most of these methods do not require special tools or skill. Common DTC codes associated with Cats: P0420, P0421, P0422, P0423, P0424, P0430, P0431, P0432, P0433, P0434
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Diagnostic Method 1: Pressure differential test before and after the cat
Diagnostic Method 2: Temperature differential test before and after the cat
Diagnostic Method 3: Remove Oxygen O2 sensor
Diagnostic Method 4: Release Cats from manifold
Diagnostic Method 5: Vacuum gauge
Diagnostic Method 6: Visual inspection
Diagnostic Method 7: Live data from an OBDII Scan Tool
Fix Method 1: Replacement with new cat
Fix Method 2: Replacement with straight pipe
0:00 Description of different exhaust system components: manifold, catalytic converter, oxygen sensors, resonator, muffler, tail pipe
4:10 Symptoms of a bad plugged cat
5:57 Procedure to diagnose a bad cat
6:00 Fix all exhaust leaks
6:20 Use a laser thermometer
9:00 Rubber Mallet test
9:57 Determine overheating condition by the discolored metal housing
10:21 Identifying a blockage or plug in the exhaust system
12:02 Drill test holes and measure pressure
12:49 Using a OBDII scan tool to check for DTC codes
13:45 Using a OBDII scan tool to check live data from oxygen (O2) sensors
15:01 Visually inspect the cats
16:20 Repairing the issue and impacts to complying with California emissions standards
17:14 Wrap up