Uh oh, it’s the dreaded P0420 (or P0430)… This Ford Taurus gave me the opportunity to discuss catalytic converter testing, as well as a chance to demonstrate an oxygen storage test. There’s a lot of misinformation in the industry about converter efficiency codes, and I’m hoping to clear up a lot of that with this case study. To be clear, this video is addressing catalyst efficiency codes ONLY, not restricted exhaust problems!
Engine Performance Diagnostics chapter 5 pages 24 - 27
- check engine light (P0420, P1000, P1270)
- replaced the failed catalytic converters
- understanding the significance of the P1000 code and how to inform your customer
- understanding how catalyst temperature is important to catalytic converter diagnostics
- using exhaust gas to heat catalysts for testing purposes
- checking for other potential faults such as faulty O2’s and exhaust leaks
- performing an oxygen storage test using propane enrichment
- using a scope to view multiple O2 sensor signals
- how O2 signals can look good but still fail a catalyst monitor
- detecting a borderline catalytic converter
- checking for external sources of catalyst failure, such as misfires and fuel trim issues
- understanding the distinction between a plugged catalyst and an inefficient catalyst
- Autel MS905 MaxiSys Mini Diagnostic System with Connector Kit - USA Version
- OTC 7148 Propane Enrichment Kit
- PicoScope 4425 4 Channel Standard Diagnostic Kit
- (Chapters 4 and 5) Fuel Trim and Oxygen Sensor Testing
- O2 sensor testing (fixed lean) P0174, P0154, P0155 - Mitsubishi
- P0133 O2 Slow Response (reversed O2 connectors) - Hyundai
- How to test an oxygen sensor on a Honda (scope vs voltmeter)
- Downstream Fuel Trim (A James Danner video review)
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
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On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
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