Code P0149A, after 02 Sensor swap?

Tiny
PACKERS27
  • MEMBER
  • 2012 FORD FOCUS
  • 2.0L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 135,000 MILES
Basically as the subject says, I was getting a P0131(I think) that indicates a possible faulty 02 sensor. I replaced it with a new one and now I have the ole P0149A. From what I've read, there's many causes to this but what is the most likely culprit? Where should I start?
Sunday, May 11th, 2025 AT 6:59 PM

8 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,137 POSTS
Yep, the ole P0149A code. This means the timing chain system, camshaft position actuator is not working correctly, It could be the engine needs oil, or the oil and filter need to be changed. If the engine has fresh oil in it then you might want to look at the camshaft oil control valve which can be clogged or no longer working, here is the location so you can check it out.

P0149A : Camshaft Position - Timing Over-Retarded (Bank 1)

Remove the oil control valves and look at the screen at the end of the valve. Check out the images (below). Please upload pictures or videos in your response.
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Monday, May 12th, 2025 AT 11:50 AM
Tiny
PACKERS27
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Are you sure you have the right code? P0149A? It talks about fuel/air ratio. What's the chance I didn't install the right 02 sensor? Sorry, I'm not questioning your experience. I'd like think I have basic knowledge but I didn't know anything about the camshaft from what I read so I just wanted to make sure we are on the same page with the code.
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Monday, May 12th, 2025 AT 12:32 PM
Tiny
KEN L
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Yep, there is confusing information on this code, Ai, might have got it wrong. Since this code came up after the sensor change, I would think the sensor is defective. I would get another (name brand) and swap it out and then clear the codes, let me know how it goes.
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Monday, May 12th, 2025 AT 6:18 PM
Tiny
PACKERS27
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  • 219 POSTS
Okay, I sure will. Thanks a lot.
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Tuesday, May 13th, 2025 AT 10:11 PM
Tiny
PACKERS27
  • MEMBER
  • 219 POSTS
I am so sorry for the confusion man. The code is not what I said it was. The code is p219a. I replaced the O2 sensor with another one, but the code did not clear itself. I erased the code to see if it will pop back up. With this code, what do you think it could be. Just to recap, I replaced the O2 sensor with a p0131 code and then afterwards I got the p219a code. What's your thoughts on it?
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Thursday, May 15th, 2025 AT 11:12 AM
Tiny
KEN L
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Np, if car repair was easy everyone would do it lol. The code

P219A - Bank 1 Air/Fuel Ratio Imbalance

Which means the system is lean and the reasons for this is the MAF needs to be replaced or there is a vacuum leak, here is a guide to help you8 and the MAF location so you can swap it out, do not clean it, it will not help, once the sensor has gone bad it needs to be replaced.

The p0131 code is for the sensor heater so it is not related to the mixture problem.

https://www.2carpros.com/articles/repair-lean-mixture-codes-p0171-or-p0174-on-some-manufacturers

We just made this video for finding intake leaks.

https://www.youtube.com/watch?v=LRKWV4Are5c

Check out the images (below). Please let us know what happens. Make sure the intake boot is connected correctly.
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Thursday, May 15th, 2025 AT 12:14 PM
Tiny
PACKERS27
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Man you are awesome. Thank you. I'm going to replace it and get back.
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Thursday, May 15th, 2025 AT 2:53 PM
Tiny
KEN L
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You are welcome, please let us know what happens.
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Friday, May 16th, 2025 AT 9:49 AM

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