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The BMW Doctor
The BMW Doctor, BMW Technician
Category: BMW
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Experience:  Over 30 years experience, 13 years with BMW, former BMW Shop Foreman, Service Manager
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what does code P0420 mean on the 2002 BMW 745LI?

Resolved Question:

what does code P0420 mean on the 2002 BMW 745LI?
Submitted: 4 years ago.
Category: BMW
Expert:  The BMW Doctor replied 4 years ago.

Hello,

 

Thank You for choosing Just Answer for your query. Yes, I can help you.

 

P0420 - Catalyst System Efficiency Below Threshold (Bank 1). This indicates that the catalyst has failed. The Engine control module (ECM) compares the pre-catalyst and post-catalyst oxygen sensor values to determine it's efficiency. It has failed to meet the parameters.

 

The catalyst is part of the exhaust manifold on this year model BMW. They retail for about $12,70 (US) and would be about 6 hours labor to replace. If this vehicle has under 80, 000 miles on the odometer and is a US specification vehicle, it should be covered under the federal 8 years / 80,000 mile emissions warranty.

 

I hope I have answered your questions and addressed your concerns, should you have any more questions regarding this matter, please do not hesitate to ask. I want you to be 100% satisfied with this answer.

 

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Thank You!

Jake

 

 

 

 

 

 

 

 

 

The BMW Doctor, BMW Technician
Category: BMW
Satisfied Customers: 2397
Experience: Over 30 years experience, 13 years with BMW, former BMW Shop Foreman, Service Manager
The BMW Doctor and 3 other BMW Specialists are ready to help you

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