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Unread 06-30-2013, 07:52 AM   #1
Registered User
1995 ZJ 
Join Date: Feb 2010
Location: Atlanta
Posts: 17
Engine code 21

On my 1995 Cherokee I have engine code 21. Points to a bad oxygen sensor.

Symptoms (other than code): On occasion while idling at a light the RPMs will drop as if the engine is quitting then it will catch itself and go away. Also have times when it falters when driving.

1. I understand there are 2 sensors on the vehicle. Anyway to know which one is bad or should I replace both or is there something else to check?

2. Where are the oxygen sensors located and how hard are they to replace?

jl-atl is offline   Reply With Quote Quick reply to this message

oxygen sensor

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