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Automatic Start/Stop Issue

13K views 21 replies 14 participants last post by  JonOrus 
#1 ·
Our turbo CX-50 has the auto start/stop for fuel savings. Yesterday coming home from a shopping outing the engine would ‘stumble’ as I was slowing down for an intersection or pulling in to the garage. It seemed to want to try to shut down even if the car rolling slowly, not just at a complete stop. Gentle pressure on the brake at a slow rolling speed seemed to trigger it. There was significant lurching as I pulled carefully in to the garage. Today the CX-50 seems to be fine. No warning lights have been activated. I should probably check to see if any codes have been triggered. Has anyone else seen this issue and had it diagnosed?
 
#2 ·
No, just had my PPT for one day and frankly, I can't tell if it auto-stopped. The button is not lit .. lol. The tach does not go to zero, does that mean it's not on? No clue, yet. Frankly, it's so hot, the a/c blows hard and can't hear the engine much.
 
#3 ·
I cant stand this feature which is why i always turn off even tho its supposedly one of the better systems..and for the minimal savings in gas versus whatever long term engine components affected..this is a EPA thing that car manufacturers are being squeezed into. .imo
 
#4 ·
There is a plug you can install to permanently disable iStop.

 
#7 ·
Just did a many hundred mile trip out and back and the i-Stop worked perfectly. Not really convinced of the value in terms of fuel savings, but it is innocuous enough compared to other manufacturer's versions.

Let me mention that it wasn't working at all initially and I used the reset procedure which is required after any battery disconnection. That fixed the issue.
 
#9 ·
Yes, i-Stop activates when the AC is running, but as per the manual the car interior must be close to the temp setting. I've also noticed that sometimes the iStop will turn off and the car cylinders reactivate if it is a particularly hot day and I'm sitting for a longer time at say a light (seems like the AC kicking in will cause that). There are also other conditions when iStop won't activate. It definitely activates less frequently if at all on short local trips like to the grocery store a couple of miles away from my home.

There's an official Mazda reset procedure, but I personally found it confusingly written and believe it or not, this video for the older Connect system works perfectly and is easy to understand (the computer-generated voice gets a little annoying):

Mazda i - Stop Initialize (Battery Initialize)
 
#12 ·
Wow. That is not true about the AC has to be off....what I have figured out is that it does have something to do with the AC. If it's really hot outside ( like it's been in Texas where I live) and you have the ac setting down on the lowest temp, it doesn't work. If it's not so hot and the ac temp in turned up, it works. The other little thing I noticed is when I stop I have to push the brake a little harder and it kicks in everytime....very weird...
My car charging does not work for my android phone.....thanks for your reply, keep me posted!
 
#13 ·
I can confirm that iStop kicks in sometimes when AC is running and other conditions are met. I think the manual says among the various conditions the interior temp of the car needs to be close to the AC temp setting--I assume that's a battery load thing. I have also noticed that sometimes the AC will cycle on at a light and that deactivates the iStop (well, starts the cylinders again), which of course makes sense.
 
#15 · (Edited)
How do we permanently turn istop off?
There are aftermarket modules which can to one degree or another be easily added to permanently disable iStop. Haven't specifically looked at any CX-50 installs though, but typically they plug into existing harnesses.

FYI there's no history of iStop causing any long term issues--well, other than driver irritation :p and that's true of this feature across all car manufacturers. And allegedly Mazda's version where it stops cylinder activity in a particular placement causes less wear and tear ultimately than other versions, like my other half's Subaru has where the starter etc is involved. I'm not convinced the actual long term fuel/emissons savings from iStop are all that valuable, but hey I guess every little bit helps and the impact adds up over multiple vehicles. And I don't find it as annoying as the Subaru version, so I just keep it on and now I don't even really notice it anymore.
 
#20 ·
Mazda's i-Stop is combustion based. As such it is significantly better than other i-Stop systems that are battery/starter based.
That is what they tell you but believe me it is both, number 1 piston is said to stop DTC just before combustion, BUT it still needs Battery and Starter to fire engine, as I have said before Australia and EU have had the Mazda i-stop for at least 5 years and most hate it as does every other car brand owner, frankly it is an unnecessary extra expense you pay for just to make emissions better and fuel economy by .01% better. (There is a i-stop steering wheel sensor at base of column that is $1000 to replace)
Plus Mazda does not permit permanent off by owner....without aftermarket. And istop Starter and car Battery is not the same as non-istops (more rugged).
 
#17 ·
This is the smoothest auto stop/start I have ever had. I actually leave it on. You want bad, try the Kia Sorento I just traded in. You let off the break, it waits half a second, then starts.

Ford's was annoying too. In my Escape, I had a plug I put into the OBD port that disabled it. There was also a way to do it with the hitch plug on the Escape. Never found a way to disable the Kia. I just had a procedure when I got in it where I disabled that and turned on LKAS. The one good thing about the Kia, it pretty much drove you when LKAS was on.

Mazda's tech on this is strange, since with Traffic Jam Assist, it DOES drive you, no idea why they turn that off at 40MPH. I loved just having my hand on the Kia wheel and being in the center of the lane at all times.
 
#22 ·
Our turbo CX-50 has the auto start/stop for fuel savings. Yesterday coming home from a shopping outing the engine would ‘stumble’ as I was slowing down for an intersection or pulling in to the garage. It seemed to want to try to shut down even if the car rolling slowly, not just at a complete stop. Gentle pressure on the brake at a slow rolling speed seemed to trigger it. There was significant lurching as I pulled carefully in to the garage. Today the CX-50 seems to be fine. No warning lights have been activated. I should probably check to see if any codes have been triggered. Has anyone else seen this issue and had it diagnosed?
Our turbo CX-50 has the auto start/stop for fuel savings. Yesterday coming home from a shopping outing the engine would ‘stumble’ as I was slowing down for an intersection or pulling in to the garage. It seemed to want to try to shut down even if the car rolling slowly, not just at a complete stop. Gentle pressure on the brake at a slow rolling speed seemed to trigger it. There was significant lurching as I pulled carefully in to the garage. Today the CX-50 seems to be fine. No warning lights have been activated. I should probably check to see if any codes have been triggered. Has anyone else seen this issue and had it diagnosed?
Hi Jerry - curious to know what was the update concerning the lurching you experienced in your CX-50?
 
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