Try one, just one.

 

Had a car once (years ago) that didn't like idling at ~750rpm. But at 850rpm everything was smooth. Of course, that was in neutral, not in D/drive.

Am no mechanic, but ...

Is this issue with the "idling" shuddering happening ONLY when the shifter is in the D/drive position? Or does it occur if in any of the other positions? (P/park, R/reverse, N/neutral, or in Manual mode.) Does it occur in "Sport" mode?

If it IS happening when in neutral, ideally without the brakes being applied, then it should be an engine question and not a transaxle question.

If putting into one of the gears (but going nowhere) it immediately begins the mild shuddering/vibration, then I'd think it's clear the issue is transaxle related. Might then be simply cured via slightly changing the "idle" RPM point by +100 or +150 rpms (which I'm assuming can be changed on these newer vehicles).

Of course, if test-driving a variety of other same-year CX-5 vehicles and you've found not a single one has the same shuddering issue at idle, then something certainly isn't right. Even if it is relatively minor, perhaps sufficiently minor that a tech can't easily identify the shuddering.

(My own "butt" meter's fairly sensitive as well, and I can generally detect minor noise, vibration and harshness, along with squeaks, in various parts of any car I'm driving in. My own personal curse, but it helps me identify issues earlier in the sequence, which has value.)

 

When comparing vehicle's make sure that it is with a MAZDA Skyactiv . The engine and the transmission are not like any other of the past Mazda or other platforms. Also the MAZDA dealerships can access the TCM as well the ECU and can see any abnormalities via live diagnostic scanning . Test driving other vehicles will not be the same in this situation unless the vibration was so bad, and at that point even a journeyman mechanic would be able to trace the cause.

I will say that the seasonal type of gasoline as well what brand can drastically effect the engine performance.

ASE

 

I’ll try change fuel then we’ll see

 

godcha, I see you are in Auckland, which dealer did you go to? How many tanks of fuel have you been thru?

I previously worked at South Auckland Motors in both Botany & Manukau.

 

I went North Harbour Mazda in Wairau. They are keep saying that no problem found..
I havent empty the fuel yet since the date of purchase but need to re-fuel soon. Any suggestion ?

 

Put a tank of BP 98 of Z 98 in it and see if anything changes.

 

I’ll try that. No Gull? And i assume that recommended fuel for cx-5 is 91 or above.
If it gets better after 98.. do you recon should go for 98 onward??

 

I've been out of the country for too long. Gull used to have a good reputation. I'm not saying it will be a fix, but try it.

A tank of 98 is a easy experiment. If it improves I would have a talk to Mazda.

 

Are you thinking to flash his ECU? That would be my thought?
Normally most MAZDA skiactiv will do better with a higher octane levels and quality gas in general. Contrary to the MYTH that they will run optimum on any octane and quality fuel. I am sure you have watched data logging and see where I am coming from on this? However if the ECU for whatever mystical reason is not running the proper fueling and timing it could account for more then normal idle engine vibrations? But I would think it would be seen in live data. Assuming the tech knows how to interpret what is being seen? HA!