Rough idle/miss fire issue (2017 CX-5)

Good morning I have a 2017 grand touring cx5 awd and my problem I have just come across is if I put it in drive or reverse (not moving ) the car has a vibration like a misfire but the minute I let off the brake it stops and car starts rolling. Also if I leave the foot on brake wile it's vibrating and touch the accelerator it will stop. I also find it worse comming to a stop with the steering wheel turned all the way. when backing in my driveway when I turn the steering wheel I can feel the vibration get worse. It feels motor related like a miss fire drives fine no bucking no loss of power no check engine light . I am do for oil change in about 300 miles was going to change out plugs and wires wile I was at it but wanted someone's opinion on this . 119k for miles. Thanks
 
It sounds like the vibration is caused by too low an idle speed when the additional load is added by placing in gear. Turning on the A/C will load the engine also. So will turning on headlights. The vibration disappears when shifting to neutral/park and/or turning off A/C. This was classic behavior before cars became computerized and today the computer maintains idle speed as electrical/mechanical loads are added. What's the idle speed when symptoms occur vs. just idling in park and no electrical loads? Has the throttle body ever been cleaned?

ETA: the steering on this car is electrical also so that's another load on the engine. And what level of vibration is occurring. I have not owned any automatic transmission car, computerized or not that hasn't sometimes had a vibration while waiting for a stoplight while in drive with my foot on the brake.
 
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To the best of my knowledge the throttle has not been cleaned I will have to have my wife put it in gear and test the battery with a multimeter to see where it drops too it makes since it sits at about 600rpm always doesn't really move much when the vibration occurs . But with these new sensors and stuff figured I'd get everyone's input Olde cars I always tinkerer with these new ones can be a giant headache though. I do appreciate all the ideas you guys came with the battery does sound right I started having problems with my cherokee a few years back and it ended up comming down to the battery also too much stuff running off the battery these days.
 
A fresh battery often Solves many unrelated issues. One year old, it should be OK.

It would be worth having a parts store put their battery tester on it to eliminate this issue. Also have them check your alternator. Turn the wheel and put it in gear to simulate the issue.

And/Or use a multi meter and check your battery voltage before starting in the morning. It should be above 12 volts. I installed 2 cheap blue tooth voltage meters on my truck. I can check each battery voltage from in the house. These cost about $15 on FleaBay. In a year or so, I'll install one on the Mazda.

Are the battery cables tight and corrosion free? The next thing to look at are the grounds on the engine. IF you live in place that treats the roads with chemicals, these can corrode the ground connections. This is very common issue on other platforms. Clean the grounds.

How many miles on the car? How many miles on the spark plugs?

Does the engine spin over quickly when starting?

Hard to start?

Also, scan for any Soft codes while at the parts store.
 
some vibration is normal. its likely the torque converter.
 
I bought it with 105k has 119 now not sure how much are on the plugs that's why I was going to change them when I do the oil change .
Plugs are so easy to change on these engines and only 4. If the miss is bothering you, do it sooner. It takes me less time to pull out my tools than to remove a plug. It might have the original plugs.

Has your fuel mileage dropped? Hard to start? Normally, worn plugs, the engine will miss when under load, hard to start and crappy fuel mileage. They will idle rough too....

I would eliminate the battery/alternator and look for soft codes in the ECU soon. If the above doesn't solve it, look at the throttle body. It might need to be cleaned. The blade might be hanging at idle.

I can't stress enough the importance for good clean connections to the battery and grounds.

Good Luck!
 
Just to give a update I tested the altinator and battery needed a altinator did that . Vibration was still their checked transmission mount it was dead so changed those thre now I have the vibration all the time now it's sounding like a grinding noise looked at it I think I found it looked the part up but all it says on mazda is rear assembly can anyone help me with this and if they have ever replaced it attaching photo and a video.
 

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Just to give a update I tested the altinator and battery needed a altinator did that . Vibration was still their checked transmission mount it was dead so changed those thre now I have the vibration all the time now it's sounding like a grinding noise looked at it I think I found it looked the part up but all it says on mazda is rear assembly can anyone help me with this and if they have ever replaced it attaching photo and a video.
 

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Looks like the vacuum pump that supplies vacuum to the brake booster for the power assist. You may find some youtube videos on how to test or change. No instructions in the shop manual?
 
Looks like the vacuum pump that supplies vacuum to the brake booster for the power assist. You may find some youtube videos on how to test or change. No instructions in the shop manual?
Not really it is one of the only things that is very vague that would exsplain why I originally was putting around at idle if I turned the wheel all the way the car would stop not stall just stop . That's why I originally started with power because of the steering being all power . I'm just thankfully everything I have replaced so far needed to be replaced
 
Looks like the vacuum pump that supplies vacuum to the brake booster for the power assist. You may find some youtube videos on how to test or change. No instructions in the shop manual?
Not really it is one of the only things that is very vague that would exsplain why I originally was putting around at idle if I turned the wheel all the way the car would stop not stall just stop . That's why I originally started with power because of the steering being all power . I'm just thankfully everything I have replaced so far needed to be replaced

Here is a link to a discussion that contains service manual links. In there, for the manual for your model car, you can find the "vacuum pump" chapters -- click.

"Vacuum Pump Inspection"
"Vacuum Pump Removal/Installation"
 
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