2021 CX-9 Burning oil

[jean-luc]

Hello! Long time lurker here. I have a 2021 CX-9 Signature and absolutely love it! I'm currently @ 9000mi and the low oil warning light came on a few days ago, confirmed by the dipstick. I did my last oil change @ 5000mi and by my estimate the car consumed around 1qt of oil in the last 4000mi. I use KNN oil filter and Castrol Edge Max Performance 5w30. No blue smoke from the exhaust so I'm suspecting the PCV valve. Any thoughts?

 

[Trixstar]

My 2019 hasn't burned much oil since new. Are you positive there was enough oil after your last oil change? 1 qt for 4000 miles is quite a bit..

 

[jean-luc]

Yes the oil level was a tad above middle of the low/high indicators of the dipstick. It was the entire 5qt jug. The pic i posted was when the car sat for 10-15 mins. When I checked the level right after driving, the oil level was actually right below the LOW indicator.

 

[dougal]

I am having a similar issue. When the car was new, the low oil light came on at about 5500 miles. It was the day before my scheduled oil change. The level was exactly as you show and I added a quart and took it in. Dealer said it was ok and first oil change should be done at around 3-5K miles. Next 5K miles was fine and I checked it every 1000 miles or so till the clock hit ~10,000 miles. Just recently, at close to 14,500 miles, the low oil light came on again and the level looks just like you show.

This is also with a white 2021 CX-9 Signature.

Part of me is happy the system is working as it should but another part of me is worried that my car is going to have serious engine problems down the road....

 

[youri]

I don’t think i have seen a lot of CX-9 oil consumption issue on the forum before.
In any case, there is a TSB out for a procedure to determine excessive oil consumption: https://static.nhtsa.gov/odi/tsbs/2020/MC-10183604-0001.pdf

With cars that new, my recommendation is always to bring it to a goos dealer. They are responsible for it while it is under warranty.

 

[PTguy]

I suggest using the Mazda oil filter. You don't want anything to complicate a warranty claim, and an aftermarket oil filter, even the top brands, might be a sticking point.

Change the oil. Get the oil level right to the hi line. Track the mileage and photograph the level on the stick each 1000 miles. Be sure the oil is at the same temperature each time. It may help to see the oil level on the stick by laying the stick on a clean white paper towel and see where the oil soaks into the paper.

The engine should use nearly no oil. I run 7500 mile oil drain intervals with almost no loss. A small amount will be burned, and a small amount evaporated, but these should be very minor. We don't yet know how much consumption Mazda North America will consider to be "normal." An engine will need to exceed that before they'll authorize warranty work.

I just looked at that service bulletin. We now know what is considered excessive...1 litre consumption in 1200 miles. That's a lot.

 

[Silly Wabbit]

There was a point in time when I wanted to create a thread like this but never got to it. I'll just add my thoughts here. Please don't make this thread into a hot/cold oil level debate.

FACT: 2.5T oil change with filter needs 5.1QT

MY reality: I changed my oil + filter, poured in 5qt, ran for 10 mins, sat for 10 mins, and got a reading of 1/4 above the low mark. I added additional 6oz (essentially 5.2qt) and checked the level to be a touch under 1/2 above the low mark.

My guestimate is you are at 5QT and you did not burn 1QT. I reckon if you add 6oz in right, it'll bring the level to roughly the half mark.

 

[speed3chris1]

Not sure why you are using so much oil but usually its rings or valve guide seals and possibly the turbo seals. PT Guy mentioned using the Mazda oil filter. I had a 2016 sig and now have a 2021 sig and both used a little oil but I was also told by the dealer if you don't use the Mazda oil filter they will not warranty the motor. Just a little food for thought. Good luck with the oil consumption.

 

[PTguy]

I was also told by the dealer if you don't use the Mazda oil filter they will not warranty the motor.

I'm not sure about that. Mazda would have to prove that the aftermarket oil filter caused the damage that led to the warranty claim. Even if the filter was not at fault, who needs the hassle of fighting it. Mazda filters cost the same as any good filter, and they even come with a new oil drain plug gasket in the box.

I just changed my oil today. After 5000 miles the level was right at the full mark with warm oil. I put in 5-1/2 quarts. The oil level should be at the full mark to start.

The question remains...where is the oil going? It isn't disappearing. Wherever it's going it is either making a mess or being burned and creating carbon that can cause a problem. I'd closely monitor the consumption, then get on the dealership to be in touch with Mazda North America to get it fixed.

 

[yrwei52]

⋯ I just looked at that service bulletin. We now know what is considered excessive...1 litre consumption in 1200 miles. That's a lot.

Yes this’s the industry standard that burning 1 quart of oil per 1,000 miles is considered normal. The manufacture won’t do anything to it unless your engine is consuming more oil. Mazda is a bit more generous, 1 liter (1.057 quart) per 1,200 miles is its guideline based on the TSB.

My past 2001.5 VW Passat 2.8L V6 was using 1 quart of oil per 800 ~ 1,000 miles since new and VWoA still refused to do anything and called it “normal”! That ended my VW loyalty for 20 years and not only got rid of the Passat early (I keep my new cars as long as I can), but also I’d never buy another VW since then.

The reason why that Audi’s 2.8L V6 on my Passat burning so much oil? The oil ring on pistons got installed upside down, and it’d been verified by some Passat owners who did the engine overhaul for the same problem.

 

[yrwei52]

I'm not sure about that. Mazda would have to prove that the aftermarket oil filter caused the damage that led to the warranty claim. Even if the filter was not at fault, who needs the hassle of fighting it. Mazda filters cost the same as any good filter, and they even come with a new oil drain plug gasket in the box.

And SkyActiv-G 2.5T uses different oil filter from the SkyActiv-G 2.5L on OEM; but on aftermarket all use the same oil filter. Mazda could use this as the excuse to refuse the warranty service on oil consumption problem, even though the oil filter should have nothing to do with it.

BTW, the free aluminum drain plug washer usually is a throw-in by the parts guy, they should charge you ~$1 for it.

I just changed my oil today. After 5000 miles the level was right at the full mark with warm oil. I put in 5-1/2 quarts. The oil level should be at the full mark to start.

The oil capacity spec by Mazda says 5.1 quarts for oil change on the 2.5T. If you need 5.5 quarts, who is right on this?

The question remains...where is the oil going? It isn't disappearing. Wherever it's going it is either making a mess or being burned and creating carbon that can cause a problem. I'd closely monitor the consumption, then get on the dealership to be in touch with Mazda North America to get it fixed.

In the case of my previous VW Passat 2.8L V6, I didn’t see any sign of blue smoke even though the engine was burning 1 quart of oil per 800 ~ 1,000 miles. Since VWoA refused to replace or overhaul the engine, and I didn’t want to keep pouring in 5W-40 full synthetic oil with risk of damaging 2 expensive catalytic converters, I chose to get rid of it early at 56K miles.

 

[yrwei52]

Hello! Long time lurker here. I have a 2021 CX-9 Signature and absolutely love it! I'm currently @ 9000mi and the low oil warning light came on a few days ago, confirmed by the dipstick. I did my last oil change @ 5000mi and by my estimate the car consumed around 1qt of oil in the last 4000mi. I use KNN oil filter and Castrol Edge Max Performance 5w30. No blue smoke from the exhaust so I'm suspecting the PCV valve. Any thoughts?

View attachment 303352

Your 2.5T is consuming 1 quart of oil per 4,000 miles? “It’s normal!” Don’t bother to complain this to your Mazda dealer. Just pour in a quart of 5W-30 full synthetic oil once every 4,000 miles.

And you do know you need 5.1 quarts of oil for oil change based on the oil capacity in owner’s manual? And 5.5 quarts if you want the oil level to reach the Max / Full / Upper mark of the dipstick.

In fact, if I were you I’d put in 5.5 quarts of 5W-30 oil during the oil change making sure the oil level is at the Full mark. I’d check the oil level often (either hot or cold, but I prefer doing it the first thing in the morning before the engine start for easiness to see the oil level on the dipstick with a single pull without wiping). This could keep the oil level above the Min mark before the next oil change without adding any oil if I use 5,000-mile OCI (although I’d set Flexible on Oil Change in Maintenance Monitor as a reference on oil life).

 

[jean-luc]

Looks like we have two factions here. I setup an appointment with my local stealership to see what they will have to say. What's odd is that if pouring in 5.1qt puts the level right in the middle of high and low on the dipstick, why would mazda give the option of a 7500mile interval if (in my case) the system would already give a low oil level warning after driving only 4000 miles? Suffice it to say, this is the first oil burner car I've ever owned.

I'm pretty sure not every CX-9 owner keeps an extra 5w30 at home or let alone knows how to actually open their engine hoods.

Mazda DOES recommend inspecting the oil level DAILY. But who the hell does this on a daily basis?

 

[jean-luc]

After much research, the answer is actually right there in the owner's manual. Now I'm thinking to just cancel my appointment and do my own monitoring for now.

 

[youri]

i wouldn’t cancel the appointment. You never know what they will say, they may take a look and find something, and at the very least you will have it on record in the mazda maintenance system that you had reported oil issues early on. That could be helpful if you ever have to get a warranty claim approved later.

 

[yrwei52]

After much research, the answer is actually right there in the owner's manual. Now I'm thinking to just cancel my appointment and do my own monitoring for now.

View attachment 303418

I agree with youri’s comment and don’t cancel your appointment. At least you have this oil consumption issue on the record, even though “it’s normal” most likely will be the answer from your Mazda dealer. While you’re there, you can mention possible coolant leak problem on the 2.5T and have them take a look on that too.

 

[jean-luc]

I'll report back this weekend. I appreciate the inputs!

 

[PTguy]

You are right, the book says 5.1 quarts. Why don't they size the system for an even number of quarts in a market that uses quart containers??? 4.8 litres isn't any better. (4.8 litres = 5.072 U.S. quarts, but we won't quibble.)

Anyway, 5-1/2 brings it to the top mark, and the car runs great. 5 quarts even is 2.3 fluid ounces short, and the car will still run great.

 

[PTguy]

A minor help for engines with high oil consumption would be to use an oil labeled for high mileage engines. It will be slightly higher viscosity, still within the 5W-30 specification, and contain products to clean and recondition seals.

 

[dynamho]

Mazda's official 2.5T symptom troubleshooting sequence for high oil consumption (greater than 1 liter per 1200 miles):

1) Check appropriate oil viscosity --> replace oil with correct grade
2) Check oil leaks around engine area --> replace leaky component
3) Check PCV valve --> replace PCV valve
4) Check internal engine damage (cylinder, piston ring, intake/exhaust valve, cylhead gasket --> replace component
5) Check turbo intake side for leaks --> replace upstream intake components
6) Replace turbo
7) Verify fix