Mazda 2.5L Turbo - Oil Fuel Dilution Issues?

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2017 CX5 AWD Touring
Any reported fuel oil dilution issues on the 2.5 turbo?

With the Honda CRV turbo oil fuel dilution causing so many problems. I was wondering if Mazda had any issues with their turbos?
 
I frequent some other forums, one specially about oil, and there has not been much info posted about the 2.5T while the 1.5L Honda comes up quite a bit. Not sure if this is because the 2.5T doesnt have this problem or because they simply sell 10X as many CRVs and were more likely to come across CRV people complaining?
 
I frequent some other forums, one specially about oil, and there has not been much info posted about the 2.5T while the 1.5L Honda comes up quite a bit. Not sure if this is because the 2.5T doesn*t have this problem or because they simply sell 10X as many CRVs and we*re more likely to come across CRV people complaining?

It's probably a little bit of both. But the 2.5T is in all 2016+ CX-9s, all 2018+ Mazda6 GT Reserve and Signature trims, and all 2019 CX-5 GT Reserve and Signature trims. I would think that if there were any issues, something would have come up by now.
 
When I've changed the oil in my 2.5T after 7500 miles the oil has looked and smelled normal. I'm thinking of sending a sample to Blackstone just to see what they say about all the conditions of the oil at that mileage.
 
ok so it seems to be an issue

so im new to this forum and this is my first post,
im the kind who will research the hell out of the thing before he buys something.
anyway , i was considering CX-5 2.5 T and came across your post in the CX5 forum and kept that issue in mind.
and behold , two weeks later , an owner of a 2018 CX-9 GT complaining about the same exact issue in the middle east.
the owner is claiming that he noticed the engine is sluggish and was noisy at around 17k Km, when he did the 20k Km service , they were able to drain 8 bottles worth of oil instead of 4 and a half ! .
he complained and just changed the oil, 3000 km again, he drains 6 bottles worth of oil , and the owner is claiming that it reeked of gas smell.

i just wanted to report this to you guys here and see your feed back , as it was mentioned before , it doesnt seem to be a well known issue anyway.
im assuming he had what you guys call it "the lemon"
i'd urge every 2.5T owner to "sniff" the oil after every oil change .
 
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ok so it seems to be an issue

so im new to this forum and this is my first post,
im the kind who will research the hell out of the thing before he buys something.
anyway , i was considering CX-5 2.5 T and came across your post in the CX5 forum and kept that issue in mind.
and behold , two weeks later , an owner of a 2018 CX-9 GT complaining about the same exact issue in the middle east.
the owner is claiming that he noticed the engine is sluggish and was noisy at around 17k Km, when he did the 20k Km service , they were able to drain 8 bottles worth of oil instead of 4 and a half ! .
he complained and just changed the oil, 3000 km again, he drains 6 bottles worth of oil , and the owner is claiming that it reeked of gas smell.

i just wanted to report this to you guys here and see your feed back , as it was mentioned before , it doesnt seem to be a well known issue anyway.
im assuming he had what you guys call it "the lemon"
i'd urge every 2.5T owner to "sniff" the oil after every oil change .


err, link?
 
ok so it seems to be an issue

so im new to this forum and this is my first post,
im the kind who will research the hell out of the thing before he buys something.
anyway , i was considering CX-5 2.5 T and came across your post in the CX5 forum and kept that issue in mind.
and behold , two weeks later , an owner of a 2018 CX-9 GT complaining about the same exact issue in the middle east.
the owner is claiming that he noticed the engine is sluggish and was noisy at around 17k Km, when he did the 20k Km service , they were able to drain 8 bottles worth of oil instead of 4 and a half ! .
he complained and just changed the oil, 3000 km again, he drains 6 bottles worth of oil , and the owner is claiming that it reeked of gas smell.

i just wanted to report this to you guys here and see your feed back , as it was mentioned before , it doesnt seem to be a well known issue anyway.
im assuming he had what you guys call it "the lemon"
i'd urge every 2.5T owner to "sniff" the oil after every oil change .

One single (and questionable) report of an issue after 3 years? That's nothing like what is happening with the CR-V.

How much oil is in a "bottle"? Did he send the oil to be tested for oil dilution or did he just "sniff" it?
 
One single (and questionable) report of an issue after 3 years? That's nothing like what is happening with the CR-V.

How much oil is in a "bottle"? Did he send the oil to be tested for oil dilution or did he just "sniff" it?

And the oil dilution tends to occur in colder climates. Last time I checked, the Middle East was not that cold...
 
No idea about the validity of this claim but keep in mind there are other reasons for fuel dilution besides poor design like a faulty injector.
 
It'd be very ironic if cx-9 had oil dilution issues. I really hope they don't. It's a different engine design than honda's, so I didnt't think this would even be possible.
Just so happens the day after tomorrow we are returning our '17 CRV Touring under lemon law for exactly that issue, and picking up cx-9 GT few days later.
I'll keep the number to my attorney just in case :)
 
No idea about the validity of this claim but keep in mind there are other reasons for fuel dilution besides poor design like a faulty injector.

Yeah, both those are generally one off things. This person is trying to insinuate that it is a wide spread issue- which it appears to be with the CR-V.
 
send report for uoa and it will show for the 2.5T. Everything else is speculative.

I did my 2.5 2018 (although its non turbo) ~3k miles, used oil analysis and after results came back there was almost not fuel detected in the used oil. That works for me.
 
Getting back to this after i forgot that i posted .
I tried to get into contact with that guy multiple time but got no answer . Later he deletes his post . So now im questioning his claim too.
Also as i mentioned earlier . Even if the claim was true . The issue is no where near what the CRV looks like .
 
Got an analysis for my 2.5T from oil analyzers... aaaand 5% fuel in 3350 miles.. ouch! (nailbyt)
attachment.php

The oil happened to be a cheap Castrol GTX magnatec. If I understand correctly, it should not affect fuel levels? Better oil should have just maintained the viscosity better.
Possibly more relevant fact was that I ran only 87 gas this time, as a low interval experiment :)
Switching to 91 and AmsoilOE, will check again in 3500.

At the same time got a report for a q5 with 70+k miles. Only 1.6% over 9500 miles. Most of the mileage was rough due to carbon buildup.
 

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oh maan... not again... now I have to check my oil. I really hope our cx-9 is fine.
I run 87 most of the time. The manual doesn't specifically say you have to run higher, just that it can't be lower than 87.
Still on original oil, and I don't remember now if I checked the level after picking it up..
I recently noticed the dealer left my tires overinflated at 54psi, so I wouldn't be surprised if oil was off, too.
 
Got an analysis for my 2.5T from oil analyzers... aaaand 5% fuel in 3350 miles.. ouch! (nailbyt)
attachment.php

The oil happened to be a cheap Castrol GTX magnatec. If I understand correctly, it should not affect fuel levels? Better oil should have just maintained the viscosity better.
Possibly more relevant fact was that I ran only 87 gas this time, as a low interval experiment :)
Switching to 91 and AmsoilOE, will check again in 3500.

At the same time got a report for a q5 with 70+k miles. Only 1.6% over 9500 miles. Most of the mileage was rough due to carbon buildup.
It's the first time to me seeing an oil analysis on a 2.5T with oil dilution issue. On the other hand we did see several reports that when they check the oil level on their 2.5T, the oil level is over the "MAX" mark. It could be caused by over-fill from factory, or the oil dilution? Only time can tell.

I don't agree Castrol GTX Magnatec is a "cheap" (bad) oil though. It's a full synthetic oil and 5W-30 is the recommended viscosity. It's API SN PLUS/ SN, ILSAC GF-5, and GM dexos1 Gen 2 certified.

I also don't believe 87-octane gas has anything to do with your oil dilution issue either. We shall see with your next oil analysis which should confirm many things. Please keep us posted.
 
oh maan... not again... now I have to check my oil. I really hope our cx-9 is fine.
I run 87 most of the time. The manual doesn't specifically say you have to run higher, just that it can't be lower than 87.
Still on original oil, and I don't remember now if I checked the level after picking it up..
I recently noticed the dealer left my tires overinflated at 54psi, so I wouldn't be surprised if oil was off, too.
How many miles on your CX-9?

There're several reports in CX-5 forum that the oil is over-filled from factory on their 2.5T. And using 87-octane gas should have nothing to do with oil dilution issue. Try to use Top-Tier gas all the time though.

For SkyActiv-G 2.5T turbo you don't get better performance with 93-octane premium gas unless you rev your engine over 4,000 rpm. For most 2.5T owners using premium gas is a waste of money.
 
I recently noticed the dealer left my tires overinflated at 54psi.

Not this again.
Tires are overinflated before shipping, to prevent flat spots from developing while on the boat. Most of us on here know that.
Checking tire pressures is part of the dealer prep checklist that's supposed to be done prior to delivery to the customer.
If the tires are still overinflated, it means your dealer tech rep was lazy, cutting corners, and didn't do their job during the prep.
He probably just looked at them, decided they were OK, and put his checkmark next to "tire pressure checked" on the list.
Stuff like this really ticks me off.
 

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