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Error code: P0171 System too lean A/F lean malfunction bank 1

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Mayo in breather pipes can be caused by lots of short journeys in the colder months. Does this sound like your journeys?

 

I'd suggest a compression or blow by test be done before condemning the engine.

Edited by smurf

56 minutes ago, smurf said:

Mayo in breather pipes can be caused by lots of short journeys in the colder months. Does this sound like your journeys?

 

I'd suggest a compression or blow by test be done before condemning the engine.

The car sat for a year, then I start using it a month ago!

Using for lots of short journeys, or occasionally for longer trips? 

 

The reason lots short trips can cause it in winter is water vapour condenses in the breather pipes when they are cold and doesn't get evaporated again by the heat from the engine, then it builds up and emulsifiers with the oil vapours. Excessive oil vapours will also accelerate this mayo building up. That is why the engine needs testing to be sure.

11 minutes ago, smurf said:

Using for lots of short journeys, or occasionally for longer trips? 

 

The reason lots short trips can cause it in winter is water vapour condenses in the breather pipes when they are cold and doesn't get evaporated again by the heat from the engine, then it builds up and emulsifiers with the oil vapours. Excessive oil vapours will also accelerate this mayo building up. That is why the engine needs testing to be sure.

I do every day 10 mile to work and 10 miles back, sometimes I do also some short journeys too on top of my work travel

2 hours ago, Sorin said:

I do every day 10 mile to work and 10 miles back, sometimes I do also some short journeys too on top of my work travel

10 miles should be plenty to get some heat into the engine. 

 

A compression test is easy, and cheap. 

Another way of checking if you got pressure building up is with engine at idle take your oil cap off do you have smoke coming out out also are you burning oil 

On 4/16/2024 at 6:46 AM, Picasso said:

Another way of checking if you got pressure building up is with engine at idle take your oil cap off do you have smoke coming out out also are you burning oil 

I went yesterday at the garage and asked them to check the compression and it looks ok. They said that there is no need to do a engine rebuild. Apparently,  the "mayo" in that breather pipe is normal as it handles oil vapours as well. Thank you all for your help!

Edited by Sorin

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