i have a liberty 2002 automatic 4x4 3.7 liters having problems first with the p0420 have read in the internet that the spark plug fouler while solve this put it like they said then a few miles later the mil came back again now with the code p0138 hope someone may help thanks in advance
code p0420 then code p0138
- Thread starter candyman
- Start date
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TAwesome
Pizza Pimp
TAwesome
Pizza Pimp
Looks like you got some bad info. Rediagnose.
1BADKJ
Full Access Member
Hotline Archive
With OEM Direct diagrams, components, TSBs, and R&R procedures Number:
345123
Vehicle Application:
2002 Liberty 3.7
Customer Concern:
Has a check engine light on with codes P0137, and P0138 for the 1/2 O2 sensor voltage high and low.
Average Reported Mileage: 70183
Tests/Procedures:
1. Check the scan data for O2 sensor voltages. The sensor should be switching from 2.5 to 3.5 volts.
2. Check the sensor signal wire Tan/White for 5 volts unplugged, Dark Blue wire should have 2.5 volts unplugged.
3. The Black/Orange wire is the heater ground and the Brown/White wire is the heater voltage which is a pulse width modulated voltage from the Powertrain Control Module (PCM).
Tech Tips:
This vehicle takes special O2 sensors, they should meet or exceed OEM specs...
In short you need a bank 1 sensor 2 Ho2 sensor
With OEM Direct diagrams, components, TSBs, and R&R procedures Number:
345123
Vehicle Application:
2002 Liberty 3.7
Customer Concern:
Has a check engine light on with codes P0137, and P0138 for the 1/2 O2 sensor voltage high and low.
Average Reported Mileage: 70183
Tests/Procedures:
1. Check the scan data for O2 sensor voltages. The sensor should be switching from 2.5 to 3.5 volts.
2. Check the sensor signal wire Tan/White for 5 volts unplugged, Dark Blue wire should have 2.5 volts unplugged.
3. The Black/Orange wire is the heater ground and the Brown/White wire is the heater voltage which is a pulse width modulated voltage from the Powertrain Control Module (PCM).
Tech Tips:
This vehicle takes special O2 sensors, they should meet or exceed OEM specs...
In short you need a bank 1 sensor 2 Ho2 sensor
i have a scan tool so i will rediagnose but im pretty sure of those code i been having somo time dealing with the p0420 put in cleaners to the gas and dont work so i use the spark plug foulers and the the p0138 apper and start to suck all of my gasoline,and i will check the voltages .thanks for your time
1BADKJ
Full Access Member
Good
