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・Fair and transparent pricing

Get a quote

What others are asking

Q: Power steering is making a high-pitched noise 2011 Chevrolet Impala

Hi there - unless the power steering has run low on fluid, there should not be air in the system. However, the symptoms you describe suggest the pump may be starved for fluid - which could occur from a low...

Q: Car jerks at a steady speed.

This may be a sign of a dirty or failing mass air flow sensor. The mass air flow sensor is a unit in the intake system that monitors air intake as it is mixed with fuel prior to being injected...

Q: Satellite radio not working

The radio is most likely the cause, since the preview channel should stay on if it was working like it should. The radio is capable of storing codes if it runs into any errors. It will need to be scanned...

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...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
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...