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After being a loyal Toyota customer for years I bought a 2019 Mazda 6 Sport about 7 months ago. This is my first Mazda and while I love the way it drives and the luxurious feel I am not impressed with the mechanical issues this brand new car has had. First, with less than 5,000 miles on the car I had a small oil leak. Then there was the recall for the issues with the cylinder deactivation. Now my oil reeks of fuel and my husband (who is a mechanic) says most likely a fuel injector is leaking and I have an appointment next week (soonest they could get me a loaner car) to bring my car in again. I have never even had to use my warranty once with a Toyota. Is this normal for a brand new Mazda or do I just have bad luck?
 

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Some fuel smell in oil is quite common in direct injection engines and does not necessarily mean your injectors are failing. Can't say much about cylinder deactivation issue, that was something mazda introduced in 2018 or 2019 if i remember. Where was the oil leak ? Someone here with 2018 has reported the same problem.
 

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@MilR -- Not on these cars. If you're having fuel dilution problems something is VERY wrong.

A leaking injector will DEFINITELY do it, however, and it's a 5-alarm "fix it now" sort of thing too, because the damage done from cylinder washdown, never mind the oil dilution and damage to lubrication, can be extraordinarily severe. The other place it can happen on these vehicles, which was just recently demonstrated, was at the fuel pump -- it has a path back into the crankcase. It's pretty easy to figure out which -- if you have a leaking injector the plug in that hole will have a materially-different appearance than the other three. If none of them show indications of a problem then it's odds-on the pump is bad.

Essentially all gasoline injection systems are subject to injector issues, however -- it has nothing to do with direct injection. The reason it's much worse when it happens with modern engines is that the fuel rail pressures are a LOT higher (as opposed to old TBI systems, for example) so very small leaks wind up resulting in very material amounts of fuel that flow through them.
 

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My 2018 2.5T has an oil leak and it is the Oil Control Valve on top of the valve cover. Interestingly enough, I just today had a bad injector diagnosis, so that will be replaced once the part comes in. My car had a MIL come on during Christmas Eve (Merry [email protected] Christmas!) and it was a misfire in cylinder #2 code. I suspect this was the culprit for the occasional VERY hard cold starts that sometimes happens first thing in the morning.
 

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After being a loyal Toyota customer for years I bought a 2019 Mazda 6 Sport about 7 months ago. This is my first Mazda and while I love the way it drives and the luxurious feel I am not impressed with the mechanical issues this brand new car has had. First, with less than 5,000 miles on the car I had a small oil leak. Then there was the recall for the issues with the cylinder deactivation. Now my oil reeks of fuel and my husband (who is a mechanic) says most likely a fuel injector is leaking and I have an appointment next week (soonest they could get me a loaner car) to bring my car in again. I have never even had to use my warranty once with a Toyota. Is this normal for a brand new Mazda or do I just have bad luck?
Sorry to hear of your troubles. I also really like the way my '15 drives. We have an '18 Camry in the household along with the 6, and we've had lots of Toyotas over the years (and Hondas and a Mazda or two), so I understand where you're coming from with your comparison.

--A small oil leak I'd write off as something that could happen to any manufacturer (and in fact it does, but that's not helpful to the person who has the leaky car).

--Cylinder deactivation is a fuel economy thing, but it hasn't worked out brilliantly for anybody who has used it, that I know of. It has drawbacks that accompany the mpg increase it provides. For most owners, it doesn't cause car-breaking problems at least within the first owner's average duration of ownership. I think we're only now getting to the point of having experience with long term cylinder deactivation on a large number of vehicles across the fleet (meaning, across all vehicles operated on this continent).

--A leaky fuel injector needs to be fixed, now. It'll be a warranty issue for you, so that's good, but it needs to be fixed. I wouldn't say this is a common thing, either, but again that's not helpful to the person who has one with a problem. FWIW, Honda is having significant injector issues on at least some models lately. Again, not helpful for you as an owner of a car with a problem.

I really, really like my 2015 6. That said, I see reports of things on the newest Mazdas that, while not necessarily massively different from the troubles that Honda, Fiat-Chrysler, or others are having lately, are disappointing to say the least. We haven't had any mechanical issues with our '18 Camry. There are things about it that are seriously annoying (like the way the idiotic 8-speed transmission and the throttle are programmed to interact when accelerating from nearly-stopped, or how there's this massive, super-bright touch screen that is the entire center console that is oppressively bright even when turned to black background if you're driving outside a city with streetlights everywhere), but no mechanical problems, nor do I expect any. The battery quit on us the other day after only 2 years, which was causing some electronic glitches, but batteries don't necessarily last longer than 2 years in this climate.

I hope you get the fuel smell or injector leak, or whatever it is fixed and that the car runs well for you thereafter.

Good luck!
 

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@MilR -- Not on these cars. If you're having fuel dilution problems something is VERY wrong.

A leaking injector will DEFINITELY do it, however, and it's a 5-alarm "fix it now" sort of thing too, because the damage done from cylinder washdown, never mind the oil dilution and damage to lubrication, can be extraordinarily severe. The other place it can happen on these vehicles, which was just recently demonstrated, was at the fuel pump -- it has a path back into the crankcase. It's pretty easy to figure out which -- if you have a leaking injector the plug in that hole will have a materially-different appearance than the other three. If none of them show indications of a problem then it's odds-on the pump is bad.

Essentially all gasoline injection systems are subject to injector issues, however -- it has nothing to do with direct injection. The reason it's much worse when it happens with modern engines is that the fuel rail pressures are a LOT higher (as opposed to old TBI systems, for example) so very small leaks wind up resulting in very material amounts of fuel that flow through them.
Maybe i'm wrong but with highly atomized fuel in direct injection engines doesn't some amount of fuel make it to the oil ? Could be just my nose but in all 4 years of ownership i've always smelt a hint of gasoline everytime i pull the dipstick. If there is a leaking injector wouldn't the oil level continue to rise ?

To OP - catch a small bottle of oil the next time you do your oil change and send it to Blackstone for analysis. From what i recall anything over 2% fuel dilution in oil is considered abnormal. Post pictures of the oil leak if possible.
 

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Maybe i'm wrong but with highly atomized fuel in direct injection engines doesn't some amount of fuel make it to the oil ? Could be just my nose but in all 4 years of ownership i've always smelt a hint of gasoline everytime i pull the dipstick. If there is a leaking injector wouldn't the oil level continue to rise ?

To OP - catch a small bottle of oil the next time you do your oil change and send it to Blackstone for analysis. From what i recall anything over 2% fuel dilution in oil is considered abnormal. Post pictures of the oil leak if possible.
The oil leak was from the timing cover. It has already been fixed. I could post a pic of the repair if you want.
 

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Well never mind. Just a look and it’s leaking oil again from the timing cover...
 

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Can you post a pic? I am curious of the exact area around the valve cover this is happening.
Same thing here, please post pictures. I recently removed the cover out of "I've got nothing else to do today" and I saw nothing out of ordinary but curious of the exact location.
 

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Maybe i'm wrong but with highly atomized fuel in direct injection engines doesn't some amount of fuel make it to the oil ? Could be just my nose but in all 4 years of ownership i've always smelt a hint of gasoline everytime i pull the dipstick. If there is a leaking injector wouldn't the oil level continue to rise ?
Nope -- that's one of those "idiot chestnuts" that people like to pass around but have no basis in reality. DI has no more propensity to do this than with any other sort of means of getting the fuel/air mixture in the cylinder and a "pissing" injector will cause severe fuel dilution problems no matter whether it's a TBI, port or DI system. In fact there should be less contamination with modern engines than the earlier ones under normal conditions, because the dead space between the top of the uppermost compression ring and the fire deck has been massively reduced over the last 20ish years for emissions reasons.

That dead space is how nearly all fuel gets into the oil in a properly-operating engine since that part of the fuel-air mixture doesn't burn. Taking care of that is part of the cat's job.

That moving of the top ring upward, however, forced tighter tolerances during assembly or you get piston slap -- ask GM about that with the 5.3L engines, nearly all of which from the early 2000s had that problem to some degree. Some were mild enough that you just got somewhat-elevated oil consumption (I own one of those and it's annoying but not bad enough for me to rip it apart, take the measurements, re-hone and then buy the correct-size pistons and have them and the rods re-balanced, plus put it back together); others were severe enough that they literally destroyed themselves, sounding like clattering diesels. The only good news with the latter is that it usually happened before you got out of warranty, frequently in the first 10 or 20k miles, so GM wound up eating it. It's also why modern engines should never be run on dino oil; moving that top ring up materially increased the temperature the oil has to survive so if you run dino oil you're begging to have sludging problems -- the partially-coked oil gets up into the valve train and makes a mess, or worse clogs the pickup screen on the pump and leads to engine failure.

What DOES contribute to problems is extensive low-temperature (e.g. cold start) operation. You have to run materially richer mixtures on a cold start which means there's excess fuel present and some of it will get into that dead space. If your operational pattern involves a lot of short trips with a cold start then you can run into trouble for that reason, but DI doesn't make it worse; you'd have the same problem even with an old-fashioned carburetor.
To OP - catch a small bottle of oil the next time you do your oil change and send it to Blackstone for analysis. From what i recall anything over 2% fuel dilution in oil is considered abnormal. Post pictures of the oil leak if possible.
If you can smell fuel in the oil it's almost-certainly bad enough to be a problem.

I've never detect ANY fuel smell in my "6" when I pull the dipstick to check oil level.

There are several people who have reported slight leaks around that oil control valve -- it's not clear if it's happening at the seal or in the valve itself (e.g. between the crimp and the electrical connector.) I have a very, very tiny weep there but then again I'm at 200k miles and not going to rip it apart over that, but if I did have a material leak there I'd change both the valve itself and the seals unless I was real sure exactly where the leak was coming from.
 

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(I)n direct injection engines doesn't some amount of fuel make it to the oil ? Could be just my nose but in all 4 years of ownership i've always smelt a hint of gasoline everytime i pull the dipstick.
GDI engines have experienced higher fuel dilution than port injected engines ever since they came on the market. That's just a fact. Different operating modes (city short-tripping in the cold, hot-weather highway driving, etc.) experience differing levels of fuel dilution relative to port injection, but the overall is higher with GDI. As GDI designs have improved, some of the GDI engines have experienced fuel dilution declines that get down closer to good port injection designs, but overall dilution is still higher with GDI than with port injection.

I'll note here that it's easy to be fooled into thinking that GDI engines don't dilute the oil with fuel any more than port injection engines if you use or look at reports from analysis labs that don't actually MEASURE fuel content. There's a well-known (on internet forums) lab out there that routinely and consistently under-reports fuel dilution by a significant amount, mainly because they don't MEASURE fuel content; they 'estimate' it based on a flash point.
 

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An effective zero is an effective zero.

BTW my PORT fuel injected Chevy 5.3L consistently shows higher dilution numbers from that "well-known" lab than does my Mazda. The truck is still within limits, but not by a lot, and it's only got 70k miles on it too. Then there is my (since-sold) pair of 150 Yamaha 4 Strokes on my former boat, one of which had a dribbler and they caught that one (which got immediately replaced, and then -- no problem since.) So much for "said famous lab doesn't pick it up with reasonable accuracy."

They also flagged a leaking injector in my Detroit Diesel powered Hatters with a pair of 6v92s in the early 2000s -- those got sampled on every change simply because (1) they required five GALLONS of oil per engine and (2) a blown up engine would have easily cost me $20 large or more to fix and God Help Me if a cam was ever damaged as they can't be removed with the engine in the boat (they have to come out the front and there's no clearance), so now you're hiring a guy with a crane that can extract it, you need a place to tear it down, etc.

So yes they do catch fuel dilution quite accurately, from first-hand experience, lab touts who may be affiliated with overpriced boutique oil company claims not withstanding.

PS: My experience with said "internet famous lab" goes back close to 20 years at this point. They've yet to shine me on although price creep will lead me to investigate others when I run out of prepaids next time.
 

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Wow, sorry to hear about all the issues. I'm approaching 170k miles and have had absolutely nothing knock on wood go wrong beyond typical wear and tear.

Mazda's Skyactive platform is doing incredibly well overall, but it's certainly not bulletproof and lemons exist out there - I hope yours isn't one and things start to behave more properly. Keep us in the loop!
 

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After being a loyal Toyota customer for years I bought a 2019 Mazda 6 Sport about 7 months ago. This is my first Mazda and while I love the way it drives and the luxurious feel I am not impressed with the mechanical issues this brand new car has had. First, with less than 5,000 miles on the car I had a small oil leak. Then there was the recall for the issues with the cylinder deactivation. Now my oil reeks of fuel and my husband (who is a mechanic) says most likely a fuel injector is leaking and I have an appointment next week (soonest they could get me a loaner car) to bring my car in again. I have never even had to use my warranty once with a Toyota. Is this normal for a brand new Mazda or do I just have bad luck?
Sounds like you've had a bit of bad luck. Bought my 2014 M6 in 2013, one of the first of the "new" design models. 123K, no major issues. There were a couple of recalls (gas cap, reflash the CPU, rear brake calipers) that had no bearing on reliability or driveability. In contrast, the last Toyota I purchased started having problems at about 70,000 miles, a weak cylinder that burned oil (I maintain my vehicles meticulously, so it was not a lack of maintenance). Considering the thousands of vehicles manufactured, each with thousands of parts, and no 2 drivers/owners are alike, there will always be a small % of problems with any brand or model.
 

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After being a loyal Toyota customer for years I bought a 2019 Mazda 6 Sport about 7 months ago. This is my first Mazda and while I love the way it drives and the luxurious feel I am not impressed with the mechanical issues this brand new car has had. First, with less than 5,000 miles on the car I had a small oil leak. Then there was the recall for the issues with the cylinder deactivation. Now my oil reeks of fuel and my husband (who is a mechanic) says most likely a fuel injector is leaking and I have an appointment next week (soonest they could get me a loaner car) to bring my car in again. I have never even had to use my warranty once with a Toyota. Is this normal for a brand new Mazda or do I just have bad luck?
Mazda is listed as the second most reliable manufacturer after Lexus by Consumer Reports. (I believe October issue). 15,000 miles on my 2018 Mazda 6 Sport. No problems.
 
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