How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Eric Your Own Question
Eric
Eric, Automotive Repair Shop Manager
Category: Cadillac
Satisfied Customers: 29949
Experience:  20+ yrs. experience as repair shop manager and technician.
3195632
Type Your Cadillac Question Here...
Eric is online now
A new question is answered every 9 seconds

CTS Cadillac: 2003 CTS Cadillac I have 2 diagnostic codes I

Customer Question

2003 CTS Cadillac I have 2 diagnostic codes I would like to explain to me of the problem.
Code's PO153 and P2099?????
Submitted: 1 year ago.
Category: Cadillac
Expert:  Eric replied 1 year ago.
HI, P0153 is for the Heated O2 sensor sensor 1. A Heated O2 sensor should constantly be switch between lean and rich signals sent to the computer(ECM). When the sensor is slow to switch, this is detected by the computer and the P0153 is set. P2099 is for the same sensor. This is set when it stays in the rich condition too long, the result from the same problem as above - not switching constantly between lean and rich. It is sticking in the rich condition. 99% of the time it is due to a faulty element in the O2 sensor and the sensor should be replaced. The other 1% of the time, there is a short in the wiring harness, usually within 3-6" of the connector. So the wiring should be physically inspected and if good, replace the sensor. Please remember to rate service using the rating page so that I may receive credit. Thanks
Expert:  Eric replied 1 year ago.
Hi, The o2 sensor in question is bank2 sensor1, which is on the driver side exhaust before the catalytic converter as shown in attached diagram Please remember to rate service using the rating page so that I may receive credit. Thanks