# 2006 Cadillac DTS - Recurring P2A00 Code

**URL:** <https://community.cartalk.com/t/2006-cadillac-dts-recurring-p2a00-code/183941>\
**Category:** Maintenance/Repairs\
**Tags:** cadillac\
**Created:** [May 2, 2022, 4:11am UTC](https://community.cartalk.com/t/2006-cadillac-dts-recurring-p2a00-code/183941 "2022-05-02T04:11:05Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Raf](https://avatars.discourse-cdn.com/v4/letter/r/848f3c/32.png) [@Raf](https://community.cartalk.com/u/Raf)\
**Post date:** [May 2, 2022, 4:11am UTC](https://community.cartalk.com/t/2006-cadillac-dts-recurring-p2a00-code/183941/1 "2022-05-02T04:11:05Z")

</div>

O2 sensor has been changed several times but code P2A00 keeps coming back… from dealership to local mechanics shop. What is going on?.

---

<div class="post-metadata">

**Author:** ![Purebred](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/purebred/32/46796_2.png) [@Purebred](https://community.cartalk.com/u/Purebred)\
**Post date:** [May 2, 2022, 10:38am UTC](https://community.cartalk.com/t/2006-cadillac-dts-recurring-p2a00-code/183941/2 "2022-05-02T10:38:09Z")

</div>

My **guess** , wire or connector from th O2 sensor to the BCM.  
I am not a mechanic, but a shop **should** have been able to figure that out.  
Of course there are other problems that could cause the code.

---

<div class="post-metadata">

**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\
**Post date:** [May 4, 2022, 1:02am UTC](https://community.cartalk.com/t/2006-cadillac-dts-recurring-p2a00-code/183941/3 "2022-05-04T01:02:35Z")

</div>

> [@Raf](#):
>
> P2A00

**P2A00 CADILLAC code possible causes**

1. Faulty Heated Oxygen Sensor Bank 1 Sensor 1
2. Heated Oxygen Sensor Bank 1 Sensor 1 harness is open or shorted
3. Heated Oxygen Sensor Bank 1 Sensor 1 circuit poor electrical connection
4. Inappropriate fuel pressure
5. Faulty fuel injectors Intake air leaks may be faulty
6. Exhaust gas leaks

Read more: [https://www.autocodes.com/p2a00\_cadillac.html](https://www.autocodes.com/p2a00_cadillac.html)

Changing it (problem #1) without finding the actual cause… could be one of #2 thru #6. Find a better mechanic.

---

<div class="post-metadata">

**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\
**Post date:** [May 4, 2022, 1:10am UTC](https://community.cartalk.com/t/2006-cadillac-dts-recurring-p2a00-code/183941/4 "2022-05-04T01:10:38Z")

</div>

> [@Raf](#):
>
> P2A00 keeps coming back… from dealership to local mechanics shop. What is going on?.

My guess, something’s not airtight between the beginning of the engine intake path and the end of the exhaust pipe. All that stuff has to be perfectly air-tight, otherwise the O2 sensor system simply won’t work. On a 2006 one definite possibility is an exhaust system leak. Especially if this car has been used for a lot of short-trip type of driving. That leaves carbonic-acid in the exhaust pipes which will eventually corrode. This sort of leak can be difficult to find, but if diligently pursued by a knowledgeable shop, will eventually turn up.

A shop with a fully functional scan tool can monitor the O2 sensor signals as the engine is run. That’d help eliminate much of the guess-work.