Air Conditioner- Weird burnt plastic smell

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Carless
I got a 2018 CX-5 with 30k in mileage.

About a week or so ago I get this weird smell when my AC is on after about 5 minutes. Its kind of a burnt rubber, burnt plastic smell kind of like burnt arm hairs.

Does anyone know what this might be or what to check for first?

Its been doing it for a week so I dont think its any oil dripping and burning but not sure either but no warning lights have came on.

Thanks
 
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Possible rodent cooking in HVAC. Happened right after a cold spell?
 
Registered to reply to this. I had the exact same issue start within the last week on my 2018 CX-5 with about 13k mileage. Started with just the burnt rubber smell after AC/heat ran for about 10 minutes. Then last night I stopped to check the mail after a 15 min drive and noticed smoke coming out from behind the headlights. No warning lights ever. Took it to the dealer first thing this morning and just got the news: engine replacement. Engine gaskets were leaking oil, which was burning. Just glad it's all covered by warranty, and my dealership gives free loaners.
 
Engine gaskets were leaking oil at 13 thousand miles? That's shocking. Consumer Reports has given very high reliability ratings to this car.
 
Just make sure it's a new replacement engine and not a rebuilt. Don't think Mazda would do that but you never know.
 
They told me it would be a new replacement. I was shocked to hear leaking gaskets at 13k miles too, but I have a good history with this service department from the '07 Mazda3 I had before this CX-5, so I have no good reason to question the diagnosis. Makes sense that the "burnt rubber" smell and smoke were from burning oil.
 
If it is AC related, it sounds like your AC clutch is going out. They make a stinky plastic smell right before they go into free wheeling mode...or lock up and burn up your AC belt.

If it's bad engine gaskets...that's weird the AC is a symptom.
 
Engine gaskets were leaking oil at 13 thousand miles? That's shocking. Consumer Reports has given very high reliability ratings to this car.

There will always be a few lemons, regardless of how high the reliability ratings are. My dad's 04 Highlander also needed a new engine due to oil consumption. The engine in that car was also used in the Camry and the Sienna, as well as Lexus' RX330, RX400h, and ES330.
 
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So I finally took it in today and sure enough same issue as you.

There was a hairline crack in the engine by the header gasket and it leaking oil towards the headers.

Engine replacement is going to be fully covered as well.

Kind of bad but glad there is no BS at this point. Seems itll be a full swap with zero out of pocket.

Only thing is the engine is like 3-4 weeks away.
 
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So I finally took it in today and sure enough same issue as you.

There was a hairline crack in the engine by the header gasket and it leaking oil towards the headers.

Engine replacement is going to be fully covered as well.

Kind of bad but glad there is no BS at this point. Seems it*ll be a full swap with zero out of pocket.

Only thing is the engine is like 3-4 weeks away.

Crack in the block, not the gasket?
 
take it to a dealership before the warranty runs out at 36k

It would of been covered under the powertrain warranty so he had another 30k miles and couple years.
I had a new engine put in my Maxima when I had about 63,000 miles on it and it was a PITA keeping track of actual mileage on the engine itself since they don't reset the odometer.
 
Just make sure it's a new replacement engine and not a rebuilt. Don't think Mazda would do that but you never know.

three questions for anyone:
  1. how would an owner know if it was rebuilt or new, other than the dealer's statement?
  2. is there some warranty requirement that a replacement engine be new?
  3. how would an owner be able to compel Mazda to supply new rather than rebuilt?
 
three questions for anyone:
  1. how would an owner know if it was rebuilt or new, other than the dealer's statement?
  2. is there some warranty requirement that a replacement engine be new?
  3. how would an owner be able to compel Mazda to supply new rather than rebuilt?

According to the 2018 Warranty Booklet (USA) (P. 18), the dealer will "either repair or replace the defective part(s) using new or authorized remanufactured parts". Based on that, I don't think the owner can strongarm Mazda into replacing the original engine with a brand new engine. That said, I have heard of people who have had success in a similar situation, where the manufacturer authorizes a brand new engine even when the warranty explicitly states that a rebuilt engine can be used. This usually comes down to the individual reps (some are willing to go the extra mile to provide excellent service).
 
three questions for anyone:
  1. how would an owner know if it was rebuilt or new, other than the dealer's statement?
  2. is there some warranty requirement that a replacement engine be new?
  3. how would an owner be able to compel Mazda to supply new rather than rebuilt?

1. Don't know, I would assume the engine would have to be disassembled to really determine. In my case I had 63,000 miles on my Maxima and the dealer obtained a salvage engine, (rear end collision that totaled the car). The engine had 5,800 miles on it. The dealer provided the paperwork so that's how I knew if was a salvage and not a rebuilt.
2. No. I would assume that if the car had really low mileage Mazda would go the extra mile and provide a new engine but if it was closer to 36,000 miles no. They could provide a re-manufactured engine.
3. Ask nicely, if you have a good relationship with the dealer they might be able to exert some pressure on Mazda. It would come down to the circumstances, age of vehicle, etc.
 
Well this is concerning. Here's a post from a Reddit user, whose dealership said there are a large number of engine failures on the 2018s, so many that engines are on back order (gotta think they were overstating it with the 50k number):

Here is my previous post from this week. As an update, on Friday the dealer informed us that the engine failure is becoming a problem for 2018 CX5. They had 50,000 up to this point with engine failures. Unfortunately the engine replacement is backordered and will take a month. We asked again for a rental and we were told they have no more rentals to loan out. The manager told us we need to escalate to corporate mazda for a better chance.

I am frustrated and do not know what to do. I plan to call the corporate Mazda number from their website and complain as much as I can to get a rental. This is really pissing me off. I am going to calm down and talk professionally, but what things can I say to make sure I do get a rental?

What other options do I really have? I feel like if Mazda wanted, they can tell me to just go **** myself and wait the damn month until they replace the engine.



Edit: I will provide an update when I call their corporate number at around 12pm EST. Wish me luck.
 
That's probably 50,000 that were recalled to get the software update for the cylinder deactivation oil pressure concern. The overwhelming majority hadn't failed, it is a preemptive measure.
 
That's probably 50,000 that were recalled to get the software update for the cylinder deactivation oil pressure concern. The overwhelming majority hadn't failed, it is a preemptive measure.
Actually, the number recalled was >260,000.

Well this is concerning. Here's a post from a Reddit user, whose dealership said there are a large number of engine failures on the 2018s, so many that engines are on back order (gotta think they were overstating it with the 50k number):

IF this is accurate [and that's a big if], Mazda is in way deep trouble.
 
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