Cold start noise cx5

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Sep 22, 2005
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New England
Vehicle: 2016 Mazda cx-5 2.5L 11,xxx miles
Cold start sounds like a can of marbles being shook around coming from engine. Goes away when I rev even the slightest bit or after like 10 seconds (feels like an eternity). Is this normal on skyactiv engines due to their filter not having adbv? Does the system have an internal valve? Is it because of Mazda’s value line (Mexico made) of filters the dealership has? Did this before my oil change that the dealer did and after I put in 5 qts qsud 0w-20 and pe01-14-302a-mv filter
 
A quick way to rule out the filter would be to switch it. I’m running the M1 EP 108A with no issues.

Of course any mechanical issues should not be ruled out but the filter change is a cheap and quick option to start with.
 
Originally Posted By: Trav
I doubt it has anything to do with the filter, it sounds like its probably common direct injector noise to me.


Wouldn't it continue past 10 seconds if it was injectors?

I agree with trying another filter.
 
No. I should have said noise due to DI, it could be the injectors themselves, pump noise at the cam at cold start or cold combustion chamber noise which is more common with higher compression ratios and DI or diesels. IIRC the Sky Active engines have a higher compression ratio of around 14:1.

In any case there is nothing that can be done about it, its the nature of the beast for some engines. If the noise was present before and after the filter was changed I doubt both filters were bad, its a vertical filter with no ADBV (according to the OP) si if that's the case how could it be the filter?
 
Originally Posted By: PimTac
A quick way to rule out the filter would be to switch it. I’m running the M1 EP 108A with no issues.

Of course any mechanical issues should not be ruled out but the filter change is a cheap and quick option to start with.

That's what I would try. Oil could be getting past an anti bypass mechanism that's leaking after an overnight shutdown. An inexpensive try. You can try using of those doctor "thingys" you put in your ears to listen for the source. I think Harbor Freight might might have a cheap version.
 
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I thought mazda played some sort of games with the valve timing on these things on cold start to get the cat up to temperature ASAP? They all sounded horrible to me when starting ...
 
My wifes 2017 Mazda3 with the 2.5 sounds positively scary on cold stars. It lasts 1-2 minutes or until it starts getting warm, then it gets very quiet pretty quickly. I've driven enough Skyactiv's either test driving or as rentals and they were all this way. It sounds like a combination of marbles in a can and a small exhaust leak. If it doesn't sound like this once its warmed up I wouldn't worry about it at all.
 
SkyActive motors vary the valve timing during cold starts to warm up the cat quickly. They do this because the cat is pretty far from the motor (by today’s standards) due to the long-tube headers. During normal operation the exhaust is better scavenged and part of the reason we can run 87 octane with a 13:1 compression ratio. It’s 14:1 in regions where higher octane fuel is the norm.

Since the OP is from Maine, I assume you know what that sounds like. Mine will do it for ~30 seconds on a typical winter morning. It does not sound like DI clatter.
 
I tried to get video of the sound but of course the vehicle didn’t want to cooperate. It didn’t make the sound today.
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You can try a filter but if it were a filter issue it probably wouldn't stop making noise one day and make it the next. Its under $10 so why not start with the cheapest thing first but I don't think you have a real issue, ask the Mazda dealer.
 
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