Thanks for the replies. We're taking it in to the Mazda dealer tomorrow. Problem is that it only does this intermittently, so it probably won't act up while we have it there.
Ok, that is a different problem. The original post did not indicate an "intermittent" condition. Intermittent by definition means that something is in the process of failing and not functioning consistently, or simply in a state of inconsistent operation.
Most engine performance issues tend to reduce down to something having to do with:
- Fuel
- Air
- Spark
- Timing
- Exhaust
- Compression
This is ground zero in most cases where most issues will lurk behind some Causation leading to some Effect. Initial checks you can make without a mechanic: Check for DTCs with an OBDII scanner (Home Screen > Applications > Select Warning Guidance).
Though your 2016 should still be well under the warranty period, if you are so inclined you might want to at least try to troubleshoot the problem to a general fault. Having the DTCs may help in this regard as it starts to point you towards the system or sub-system possibly containing the malfunction. The nature of the DTC can help in determining the potential type of problem (mechanical, electrical, etc.).
Having a Mazda 2016 CX-9 Workshop Service & Repair Manual would not hurt either - probably worth ordering from your dealer. Again, your 2016 is still under warranty and should ultimately be taken back to the dealer for repairs. However, when you do go back, you want to arrive in the service department having as much information about the potential problem as possible and at least trying to troubleshoot the matter (if at all possible) before hand could help.
There is a difference between arriving at your dealer and telling them you have a "loss of power when you step on the accelerator pedal" and "There is an intermittent voltage irregularity going into the EGR Value. The result seems to be an intermittent loss of power on acceleration."
There is a lot going on in front of and behind the new iSkyActive-G turbo charger to keep it spooled up at lower RPM. The new EGR design plays a role on the intake side to help keep temperatures low by routing exhaust gasses through the intercooler, but the controlled exhaust ports also play a vital role in keeping the turbos spooled as well. Both of these sub-systems would have a definitely impact on throttle response if either were malfunctioning. If the DPT value (Dynamic Pressure Turbo) which is normally constrictive at lower RPM, is somehow not opening as designed when you place a demand on the throttle, that would seem like a potential cause for "loss of power" as that 17+ lbs of "instant boost" is necessary to get things going. Without it, you could be experiencing severe lag.
However, one of my initial concerns with this new iSkyActive-G design was its Direct Injection design. A lot of engines on the market these days are now direct injection and some of them suffer from carbon build-up on the back side of the values at relatively low mileage - leading to power loss. However, the kind of losses you are describing make carbon build-up on the valves as the exclusive causation seem fairly remote - but we don't yet know what the felt effects of direct injection carbon build-up on values will be with the iSkyActive-G because it is still a relatively brand new engine design. Time will tell and I am paying particular attention to my Valves along the way.
Still, as someone has already stated here, being a 2016 CX-9 and having that kind of struggle in producing power under throttle makes me think in terms of ECM. As a sanity check, you can easily check the upper air intake system components for blockages (air cleaner body bottom, air filter, air cleaner body top, air pipe, air inlet hose, mass airflow sensor).
Given the age and miles on the vehicle. This will probably turn out to be a really easy fix once you get a good trained mechanic troubleshooting it.