Do the european emission standards impact catalyst life in oil burners?

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I was having a discussion about passing this year's emission testing and the topic of catalyts being damaged by oil burners came up. It was mentioned that as long as a car is Euro 3, oil burning shouldn't matter in passing the test and that using ACEA A/B oils would be fine. Personally, I don't think it matters if a car is Euro 1 or Euro 6, if it's burning oil, that catalyst will have reduced efficiency and lifespan and will make it harder to pass the test. And in any case, using an ACEA C oil would help in a mild case of an oil burner.
As an aside, is there a threshold for oil burnt per given distance that would start damaging the catalyst?

Euro Standard Chart_Tdga8UX3.jpg
 
While burning oil does slowly deactivate catalysts over time, but temperature is a bigger factor. I haven't looked at European emission standards lately, but if they are similar to EPA/CARB, emissions tests are conducted with end of life catalysts. That way, vehicle start out producing less emission and then over time they end up at what they were certified at. But to be more specific, I don't think there is any requirement to complete emission certification on an engine that is at the end of its life. If a car is burning 1qt/1000 miles, that is still only 1qt of oil to 160qts of gasoline in a car that gets ~25mpg, or 0.625% of the fluid consumed. I believe there is more test to test variation in emissions produced then you would get accounting for oil burn.
 
I don't know how things are now but the last vehicles I had emission tested were in 1980 in Arizona.

Back then, vehicles had to pass the emissions requirements of when the vehicle was produced. Since my vehicles had no emissions requirements, they weren't required to pass any. My vehicles did fail the standard test's. They gave me a print out of my failed test's and on the back it listed things I could do to help pass the basic test. They told me to perform the required maintenance items and return for a free retest.

I filled out the back of the form and returned for a retest. Both vehicles failed again and I was told have a nice day.

Emission testing was a money tax for the state and they were just interested in sticking everyone with a vehicle for $10.00.
 
I was having a discussion about passing this year's emission testing and the topic of catalyts being damaged by oil burners came up. It was mentioned that as long as a car is Euro 3, oil burning shouldn't matter in passing the test and that using ACEA A/B oils would be fine. Personally, I don't think it matters if a car is Euro 1 or Euro 6, if it's burning oil, that catalyst will have reduced efficiency and lifespan and will make it harder to pass the test. And in any case, using an ACEA C oil would help in a mild case of an oil burner.
As an aside, is there a threshold for oil burnt per given distance that would start damaging the catalyst?

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Where are you located, and what is actually tested in your location?

Where I am, they test for lambda value (between 0.97 and 1.03) and CO emmisions. Either on idle (older cars) or at raised rpm.

cats rarely if ever die, they tend to break from overheating or impact. Acea C oils matter little in gas engine catalyst protection, the calcium or magnesium is not hurting catalytic converters and phosphorus levels are only slightly lower. It's the phosphorus that hurts cats, but it's also the phosphorus and calcium that protects engines from wear.

Most often it's the oxygen sensor in the exhaust that causes failed emmisions tests
 
For what it's worth in this discussion, the one and only time I saw a vehicle with a catalyst efficiency code due to oil consumption was in a car that burned in excess of 1 quart in 500 miles. He was using an HDEO as well and it likely had over 1000 ppm of ZDDP.

I don't know the exact consumption but it definitely was more than a quart in that 500 miles.
 
My previous 2005 Nissan Primera 1.8L burned oil about 0.3l/1000km (1qt/2000miles) from 160k km to 340k km until the engine finally gave up. So 180k km of oil burning.

It still passed exhaust pipe emission tests (Finland, Europe) with flying colors with the original catalysator. So my experience is that a cat can withstand surprisingly lot of beating before clogging up. Oil used was synthetic ACEA A3/B4 5W-40.
 
Where are you located, and what is actually tested in your location?

Where I am, they test for lambda value (between 0.97 and 1.03) and CO emmisions. Either on idle (older cars) or at raised rpm.

cats rarely if ever die, they tend to break from overheating or impact. Acea C oils matter little in gas engine catalyst protection, the calcium or magnesium is not hurting catalytic converters and phosphorus levels are only slightly lower. It's the phosphorus that hurts cats, but it's also the phosphorus and calcium that protects engines from wear.

Most often it's the oxygen sensor in the exhaust that causes failed emmisions tests
I'm from Bulgaria and I'm pretty sure only what is listed in the attached picture is tested for.
I'm unsure about the validity of the test, given that CO and HC are literally zero, but it's just an example.

File_20240808-011457.webp
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so are you saying if the car is E3, E1 or E6, the oil burning will not affect the CAT's emission or if the car is E3 and above oil burning will not affect the CAT's emission?
lambda >1 is a lean condition which tends to be the trend for most FI cars >1990
 
It's my opinion that oil burning affecting catalysts and emissions is independant from the Euro rating of that vehicle.
From what I gather he meant as long as a car is Euro 3 or above, that oil burning is a non-issue, which I don't agree with.
 
My thinking is that oil burning is always an issue for catalytic converter. But just how big?

For example, many brand new Volkswagen engines burn oil straight from the factory, from 0.1l up to 0.5l per 1000km. And even so the cats seem to withstand that easily at least for 150kkm and maybe much longer. And people still continue buying these brand new WVs every year, even if they are notorious oil burners: ”It’s a feature, just pour a quart of new oil to sump and continue driving”. And people seem to be happy with their cars, haven’t heard people complaining about fouling VW cats.

So imho, cats can take surprisingly lot of beating if oil burning isn’t overly excessive. ACEA C3 oil used in modern engines of course helps here, being mid-SAPS, compared to older ACEA A3/B4 which is high-SAPS.

”Engine oils with a lower amount of phosphorus and sulfur are called low-and mid-SAPS oils, also low-ash oils. These oils belong to the C category in ACEA’s oil classification, where “c” stands for catalyst-compatible.”
 
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Where are you located, and what is actually tested in your location?

Where I am, they test for lambda value (between 0.97 and 1.03) and CO emmisions. Either on idle (older cars) or at raised rpm.

cats rarely if ever die, they tend to break from overheating or impact. Acea C oils matter little in gas engine catalyst protection, the calcium or magnesium is not hurting catalytic converters and phosphorus levels are only slightly lower. It's the phosphorus that hurts cats, but it's also the phosphorus and calcium that protects engines from wear.

Most often it's the oxygen sensor in the exhaust that causes failed emmisions tests
so true! it happened to me after my 2 times replacing new injectors
 
Think diesel car smog test is more strict than gasoline cars here in Finland, full throttle for about 5-10 sec 3 times when they measure KV Value. But overall its easy to manipulate those tests legally.
(Hilux) for that truck is max KV value is 3.0, with Neste HVO i get 0.52, normal diesel i get 2.9-3.4 KV value
 
For what it's worth in this discussion, the one and only time I saw a vehicle with a catalyst efficiency code due to oil consumption was in a car that burned in excess of 1 quart in 500 miles. He was using an HDEO as well and it likely had over 1000 ppm of ZDDP.

I don't know the exact consumption but it definitely was more than a quart in that 500 miles.
I had a vehicle that failed the emissions test due to catalyst efficiency. It was a 78 Ford Fairmont, and it did consume over 1 qt of SAE 40 every 500 miles.
 
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