0 votes

2002 Toyota Celica with codes P0420 and P0171, what do the codes mean?

Vehicle: 2002 Toyota Celica

1 Answer

0 votes
by (11.5k points)
The P0420 code is a bad catalytic converter code. This means the converter is not working efficiantly enough to make the rear O2 sensor happy. In most cases a new converter is in order.

The P0171 code is a lean mixture code on bank 1. There are several causes for ythis type of code. Most common cause is a vacuum leak, low fuel pressure or a possible mass air flow issues.

Related questions

0 votes
1 answer 207 views
0 votes
1 answer 962 views
asked Nov 16, 2017 by anonymous
0 votes
1 answer 2.3k views
+1 vote
1 answer 57 views

37.5k questions

30.8k answers


20.6k users

Need A Repair Shop?
Find local automotive repair shops in your area.
How much do you know about cars?

Take the AutoCodes.com automotive tests and turbo-charge your car repair knowledge

Play Now

Home - For Shop Owners - About AutoCodes.com - Privacy Policy - Terms and Conditions - AutoCodes.com Feedback - Copyright 2010-2020 AutoCodes.com

AutoCodes.com - Engine-Codes.com - Infinitihelp.com - Nissanhelp.com