p0420 & p0430 on volvo xc90 2012 Topic is solved

[MoVolvos]

Can you explain me the difference between 0w40 to 15w40?

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Below is the 2012 XC90 Manual for download. 0W ~ 15W has to do with the viscosity property at colder temps. The second rating has the do with the higher temp characteristic. Since your engine is burning oil a higher viscosity will help with the blowby from worn rings if that's the cause. The higher your climate ambient the higher the first number. The same with the second number of 40W. Wouldn't go with any 5W or 10W-30 as the motor gets older and looser.

In 2012 Volvo was still working with API SL. The newer API will have slightly different characteristics but a good oil like Rotella T6 in the 5/15W40 in general will be excellent for the engine.
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API Service Categories
https://www.api.org/products-and-servic ... b-gasoline
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Shell Rotella® T6 Full Synthetic
https://rotella.shell.com/en_us/product ... hetic.html
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2012 XC90 Owner's Manual
https://volvo.custhelp.com/app/manuals/ ... model/XC90

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2012 XC90 Manual Page 214.png (408.18 KiB) Viewed 1400 times

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[EgoziAlon]

Would you recommend this oil:
Castrol Vecton 15W40 CK-4/E9 5L
?

[MoVolvos]

Would you recommend this oil:
Castrol Vecton 15W40 CK-4/E9 5L
?

Either one should be fine. There is a multi-fuel and one for diesel in the 15W40 but either is okay. Sometimes oil manufacturers doesn't apply for an API Rating so they can have a larger product line. The old stock Rotella T6 use to have an API SN but removed it in the newer bottles so they can make way for the newer Rotella Gas Truck oil. According to Rotella the T6 formulation didn't change.

https://www.castrol.com/en_us/united-st ... ecton.html
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[chitownV]

In the 3.2, the issue isn’t blow by. This isn’t a 5cyl turbo engine. The issue is carbon build up blocking the oil drain holes in the pistons. Typical 15W-40 oils fall in the higher 40 weight hot viscosity range. Also, as is very well known in the 3.2, 3.0 T6, and 2.0 engines, the PCV can cause oil consumption as well as P0420/P0430.

Here’s a reference thread
https://www.swedespeed.com/threads/3-2- ... on.658144/

Learn more about A3/B4 oils and the right oils for the 3.2.
https://www.swedespeed.com/threads/oil- ... st-8046070

You do not want to use a diesel oil, especially if there is less oil regulation than the U.S. and E.U. Those oils typically have higher metal and additives that can contaminate the catalytic converters. While this has reduced with newer oil specs, it’s not something I would recommend with existing P0420/P0430 codes.

[chitownV]

BTW EgoziAlon,

I mentioned before if you could go look at your XC90 to help provide more information. These are easy and a good start…

1. Did you smell the oil? If a little sweet, then perhaps coolant (white residue on spark plugs). If you smell fuel, then you are running rich (air/vacuum or fuel issue; P0420/P0430 code). If you smell something that stinks it could mean someone used RTV (you smelled something burning up front) or you have bad gas.

2. Could you take a picture of the new catalytic converters that were installed.

3. You said you smelled an oil burning smell in the front. Was reduced changing from 5W-30 to new 0W-40 oil.
Have you looked under the hood for any oil leaks, such as the common brake vacuum pump or the serpentine decoupler (both very well known to leak without preventative 100k mile maintenance replacement). I suggested you could take pictures of the engine areas with flash and then zoom in. Your significant oil consumption could have contributions from very well known seals that will leak oil if they were not changed. Since you said the previous owner, as well as you, hasn’t done much maintenance, you should take pictures and share them.

[MoVolvos]

In the 3.2, the issue isn’t blow by. This isn’t a 5cyl turbo engine. The issue is carbon build up blocking the oil drain holes in the pistons. Typical 15W-40 oils fall in the higher 40 weight hot viscosity range. Also, as is very well known in the 3.2, 3.0 T6, and 2.0 engines, the PCV can cause oil consumption as well as P0420/P0430.

Here’s a reference thread
https://www.swedespeed.com/threads/3-2- ... on.658144/

Learn more about A3/B4 oils and the right oils for the 3.2.
https://www.swedespeed.com/threads/oil- ... st-8046070

You do not want to use a diesel oil, especially if there is less oil regulation than the U.S. and E.U. Those oils typically have higher metal and additives that can contaminate the catalytic converters. While this has reduced with newer oil specs, it’s not something I would recommend with existing P0420/P0430 codes.

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Below is from the 1st link you provided. The 2012 XC90 3.2 didn't have the infamous oil rings. It's from long intervals between oil changes so wear. I am sure there could be other issues but it's best for the O.P. to try the simple things first.

1) Clean the CAT with Lac.
2) Replace plugs
3) Use Premium fuel
4) Use a thicker oil & 5K intervals

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https://www.swedespeed.com/threads/3-2- ... on.658144/

2) Engine Oil Changes

Volvo did a disservice with their ~7k mile oil change intervals using conventional oil. Servicing a 3.2 at the dealership can lead to issues IMHO.
(Edit, added questions & answers below)

Q: Do all 3.2s consume oil?​
A: No. Many don't have a consumption issue due to good oil changes. A link discussing high mileage 3.2s posted later in this thread​
​
Q: Does it matter which year 3.2?​
A: No, real-world feedback from owners shows the same results and application for both variants of the 3.2 engine.​
​
Q: Is there an engineering flaw?​
A: Not really. unlike the P3 platform 2.0 (forced induction) and 2.5t engine which saw oil consumption as early as 30k miles and 60k miles, if there are poor oil changes that contribute to oil consumption, it's not usually seen until over 100k miles. The 3.2 is a naturally aspirated engine (no turbo or forced induction).​

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[EgoziAlon]

The cat is new
The plugs are new - the plugs in the picture are the old ones
In Israel we have only premium fuel -95 octane or 98 octane both unleaded
And about the oil, it's right now 0w40. I will try and change to your recommendation.

[EgoziAlon]

BTW EgoziAlon,

I mentioned before if you could go look at your XC90 to help provide more information. These are easy and a good start…

1. Did you smell the oil? If a little sweet, then perhaps coolant (white residue on spark plugs). If you smell fuel, then you are running rich (air/vacuum or fuel issue; P0420/P0430 code). If you smell something that stinks it could mean someone used RTV (you smelled something burning up front) or you have bad gas.

2. Could you take a picture of the new catalytic converters that were installed.

3. You said you smelled an oil burning smell in the front. Was reduced changing from 5W-30 to new 0W-40 oil.
Have you looked under the hood for any oil leaks, such as the common brake vacuum pump or the serpentine decoupler (both very well known to leak without preventative 100k mile maintenance replacement). I suggested you could take pictures of the engine areas with flash and then zoom in. Your significant oil consumption could have contributions from very well known seals that will leak oil if they were not changed. Since you said the previous owner, as well as you, hasn’t done much maintenance, you should take pictures and share them.

I will do the checking later today hopefully.
But how can i take pictures of the new catalytic?
I will take general pictures of the engine - any way there are no any leaks

[MoVolvos]

The cat is new
The plugs are new - the plugs in the picture are the old ones
In Israel we have only premium fuel -95 octane or 98 octane both unleaded
And about the oil, it's right now 0w40. I will try and change to your recommendation.

.
Although the CAT is new try cleaning and see if the codes go away. If it does then change the oil to see how long before or if the code returns. Do one thing at a time so you know what each changes made. If the 0W40 is dirty already consider it a flush oil and change it after the Lacquer Thinner cleaning.
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[EgoziAlon]

How do i use this Lacquer Thinner?