2016 CX-9 Loss of Power

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seplant

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Mazda CX-5
Anyone else experiencing intermittent loss of power with the newer model CX-9? We just hit 20,000 miles, and just started experiencing almost complete loss of power when we try to accelerate. We can press the accelerator to the floor and get literally 20 mph. The engine doesn't rev all the way up, it just drags. It eventually can get up to about 40 mph, but when it is doing this, that's about it. The problem comes and goes. Most of the time it seems okay. Could be happening after heating up, after driving for an hour of more.
 
Still under Manufacturer's warranty, take it to Mazda for diagnosis...don't try to work on it yourself or take it to a regular garage.

Mazda has the diagnostic tools plus it would cost nothing.
 
Sounds like a boost leak. Check for loose or slashed/broken intercooler pipes or an exhaust manifold or housing leak (Due to rust or backed out bolts). Or just take it to Mazda.
 
Sounds like a boost leak. Check for loose or slashed/broken intercooler pipes or an exhaust manifold or housing leak (Due to rust or backed out bolts). Or just take it to Mazda.

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.
 
I had a weird thing were the car had an intermittent surge. It only did it twice, and of course dealer couldn't replicate it.

It went away and since then I have been putting in Techron once a month to clean things out.
I don't know if that is the fix, but the consensus amongst experts is that adding Techron occasionally or using top tier gasoline on a regular basis maintains performance and diminishes deposits.

Let us know what the dealer says.
 
I sincerely hope we don't have the same carbon buildup on the intake valve issues that other di cars have. If this is an issue already- it's not going to look good with mid life mileage.
 
No reports of carbon on the backs of the intake valves. In any case, that wouldn't be the same as seplant is reporting.

Carbon on the backs of the intake valves is a result of the engine's crankcase breather system not adequately removing oil vapors before venting to the intake, plus direct fuel injection where no gasoline is in the intake air to wash off these valves. I think most engine makers have corrected this problem.
 
The dealer says the computer in the vehicle reported codes that they are working with Mazda to decipher. Hopefully will have some answers tomorrow.
 
No reports of carbon on the backs of the intake valves. In any case, that wouldn't be the same as seplant is reporting.

Carbon on the backs of the intake valves is a result of the engine's crankcase breather system not adequately removing oil vapors before venting to the intake, plus direct fuel injection where no gasoline is in the intake air to wash off these valves. I think most engine makers have corrected this problem.

PTguy- The issue with direct injection vehicles has always been that the fuel does not hit the back of the intake valves and therefore, carbon and other contaminants build up. When the carbon builds up, it prevents complete detonation of the fuel and leads to fault codes, drive ability issues, and decreased power. The PCV issues you are talking about are due to oil, not fuel and incomplete combustion. This issue still remains with Audis, BMW's, Mercs and many other manufacturers of new cars.
 
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The dealer says the computer in the vehicle reported codes that they are working with Mazda to decipher. Hopefully will have some answers tomorrow.

Sep, did they provide you with the codes by chance? Can you get them and post them? Just curious as to whether they are related to detonation.
 
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Sep, did they provide you with the codes by chance? Can you get them and post them? Just curious as to whether they are related to detonation.

The dealer still has our CX-9, and we have a loaner vehicle. I haven't spoken with them since the initial report. Apparently Mazda is still trying to figure out what needs to be done. I'll see if I can get the codes on Monday.
 
I had a very similar problem a couple of months ago..
CAREFUL

I have a '16. Over the past few months, I've been moving to 91 and then 93. I'm on my 3rd or 4th tank of 93 - on Monday I experienced a pretty massive computer failure. The car went into limp mode, and I was able to make it home going 15mph. I had it towed yesterday to the dealer, and they're doing a fairly significant investigation into why it happened. They believe it's fuel related, but it's not "bad fuel" - it's something else. While Mazda corporate is trying to figure it out, the local tech said there's no reason to put 93 in the car - anything above 91 is "too rich" and a "waste". He does suggest 91 over 87, though.

I'm currently in a loaner. I'll let you all know what they come back with.

Turns out they (Dealer, Mazda Regional, Mazda USA AND Mazda Japan) have absolutely no idea what caused it, so they replaced the knock sensor and the ENTIRE EXHAUST MANIFOLD. Pretty crazy.

I'd like to note that Mazda had to hire translators to get the Japanese engineers on the phone with the local dealer techs.

The car was in the dealer for over two weeks. I have it back now and it's running flawlessly, but I'm not convinced they solved the actual problem.

PM me if I can be of any help.
 
wraith, the carbon comes from the oil from the crankcase breather. There is no other place for a carbonaceous substance to come from in a DI engine's intake manifold. The oil mist hits the hot intake valve and bakes into carbon.
 
The Mazda Field Engineer for North American Operations directed our dealer to install a data recorder and have us use our CX-9 as normal to try and capture data on the issue. Apparently the codes that the dealer read were meaningless. We'll see what happens.
 
I experienced loss of power on accel the other day...I didn't mash the throttle, but instead gave it a slow but heavy dose of the pedal...An odd noise emitted on loss of power (maybe boost leak?)...i let off and all was fine. I had been running whatever 87 octane (and noticing some uneven boost) so I'm on 93 now with no further issues and smoother boost.
 
Update on my situation. The dealer has had our vehicle for over two weeks now. They had us driving it with a data recorder installed, but after experiencing several "limp mode" incidents, they asked to keep it and gave us a loaner CX-9. After sending the data recorder back to the Mazda engineers, the dealer was asked this week to install a different data recorder and try to reproduce the issue themselves. The issue tends to happen after driving for a while, but they apparently haven't driven it much, so they haven't been able to make it happen yet. Plus, if the issue is heat-related, the weather here has been cool lately, so it may be more difficult to reproduce. They think the issue might be related to a sensor - either a bad sensor or the software reacting incorrectly to the data from the sensor.
 
Well, we had a happy ending. The engineers couldn't figure out the problem with our CX-9, so Mazda offered to buy back our vehicle and replace it with a new one. They gave us top dollar to trade my 2016 CX-9 (with 20,000 miles and engine issues) plus they gave me a boatload of incentives. We just picked up our brand new 2017 CX-9. Mazda did us right!
 
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.
 
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