Skip the auto shop - Our mechanics make house calls

Q: Code P0158 after sensor swap

asked by on

I had a code P0420. After speaking to multiple parties, I decided to replace my O2 downstream sensors (as my FlashPaq reader told me it was a downstream problem). I replace the passenger side, and the sma score came back. Now I've replaced the driver side, and I'm seeing code P0158 high-voltage something-or-other. How do I fix this? Where do I go from here? Do I need a new catalytic converter? I'm trying to fix this problem without taking it in and paying a bunch of money, but I don't know how to proceed. Thanks, Johnny

My car has 56000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. I suspect your &...

Hi, thanks for writing in. I suspect your "upstream" sensor is the primary problem, and should be replaced. The downstream sensor you did replace is really measuring whether the catalytic converter (the main cat, not the pre-cat) did the job to clean things up. But the upstream O2 sensor does the heavy-lifting to tell engine management to lean things our, making the catalytic converters job easier. There is also a Jeep Customer Satisfaction program (CSC-10042886-7723) to re-program the software for the downstream O2 sensor to check more often under certain circumstances when the down stream sensor becomes slower to respond (as it ages). I recommend checking with Jeep for the Customer Satisfaction O2 Sensor reprogramming.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Airbag light stayed on after battery change

The light might have came on before you disconnected the bad battery due to low voltage to the system. Once you put in the new battery, the system still has a stored code and the light will be on until...

Q: Sun roof won't close and I can hear a click from the roof but nothing happens.

Hi there. Check the sunroof track and see if anything is in its path. Old dirt can cause the sunroof to not open and make it stick. If the track is clean and clear, then most likely the motor to...

Q: Rattling noise in neutral. Car won't go over 30mph in 3rd.

Hi thanks for the question, man, there is nothing worse than a car that won't go anywhere when we want or need it to. It sounds like you may be having a problem with your catalyst converter in your exhaust....

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...