Stumble @ Idle
- Thread starter smmra
- Start date
Maybe not. I noticed that with my elantra, everyone called me crazy. At the same time of me first feeling that I noticed my plugs where white, showing lean. After starting to reset the ecm about every two weeks the car seemed faster and the plugs stayed a nice grey color. Someone reset and ecm at the track and dropped dang near half a sec in the 1/4. People still said we where crazy. Then someone got on a dyno. Reset the ecm and gained 5whp and 5lbs of torque. Not much you say, but when that was a 5lbs gain was just at peak. Much more torque below 3kand right up to peak after the reset. Why? The ecm learns lean to make better gas mileage. The peak numbers (hp @ 6000rpm and trq @ 4500) didn't change much because after 4.5k it was still a little rich to protect the motor even with the lean corretions. Right after a reset ill get 33mpg on the highway (dead on what the EPA rating was) Give the car a week or so to "relearn" its map correction and I can pull as high as 37 (normally 35.5). So I can make my car a little faster with a reset or leave it alone and get better gas mileage. I just wish I could make it happen with the flip of a switch. Still working on that. 
I just learned about the concept between Open and Closed Loop in the ECU. My 5 did the little hiccup this morning (64*F), after only about 2 miles of driving… however it was enough that the temp gauge was sitting right in the middle. Because it seems that this happened JUST as the engine got warmed up, the transition from open to closed would’ve happened at the same time of the stumble. Also, while rare this sometime happens to people after they’ve been driving for a while but just in really cold weather… the ECU can go back into Open loop if the intake air would be cold enough or under some throttle conditions. This led me to speculate that maybe it’s the transition of the ECU from open loop to closed loop operation that’s the root cause?
I’m planning on getting a Scangauge II at some point in the future, and one function it’ll display is whether the ECU is in open or closed loop. This would be very interesting to see if it’s the cause of this freekin issue.
I’m planning on getting a Scangauge II at some point in the future, and one function it’ll display is whether the ECU is in open or closed loop. This would be very interesting to see if it’s the cause of this freekin issue.
mountjonas
Member
- :
- 2013 VRM MS3
my wife's 5 stumbled once about 6 months ago when i drove it. didn't think much of it. then it did it twice, yesterday and today when she was driving on the freeway. it's about 80 where we live, car was warmed up and she was slowing down for traffic and said it felt like the car almost died. 20k miles on her 5. maybe a trip to the dealer is in order.
My idle runs very low when I am stopped and about once a month, when I accelerate from a stopped position, the car will begin to accelerate and then cut off for a fraction of a second which could be quite scary if you are making a left turn with on coming traffic.
Took it into the dealership for my first service and mentioned the issue. They checked for flat spots in the power on take off and updated the software for the PCM.
It runs smoother now in general. Hopefully it solved the problem. If it didn't I'll post an update here.
Took it into the dealership for my first service and mentioned the issue. They checked for flat spots in the power on take off and updated the software for the PCM.
It runs smoother now in general. Hopefully it solved the problem. If it didn't I'll post an update here.
my wife just came to me about this problem in her 5... it was not cold out when it happened and the car was at normal operating temp. we have had the car for a year and this is the first time we have had this happen.
now that i see that we are not the only ones to have this happen, i am going to call the dealership. i would guess that it will be a dead-end talking to them... but at least it will start a paper trail so there wont be any warranty issues later.
now that i see that we are not the only ones to have this happen, i am going to call the dealership. i would guess that it will be a dead-end talking to them... but at least it will start a paper trail so there wont be any warranty issues later.
I'm sick of this crap with Mazda allegedly not know ing what the problem is, or how to fix it! They've had enough customers complain about it already!! It's happened to me too many times, but only max of once/day, usually first thing in the morning, less than a km from start. It's even happened a couple of times in the afternoon driving home from work (on the highway doing about 130km/hr). If it's happened to you, you know it scares the crap out of you!! I've had it in the dealer 3 times for this issue, and even called Mazda corp head office. Obviously it would cost them too much to fix (maybe a new ecm?), and don't want to bother with it. Currently, I'm looking for an external ecm programmer so I can reprogram it myself (while still being able to switch back to factory settings). this way, I can get more horsepower which it desperately needs!
I've already changed the muffler and installed a cold air intake, which definitely makes a difference in power, but want more!!! Other than that annoying jerk, the car's been great!! - 2 years old, 48,000km
I've already changed the muffler and installed a cold air intake, which definitely makes a difference in power, but want more!!! Other than that annoying jerk, the car's been great!! - 2 years old, 48,000km
maple_leaf
Member
- :
- Mazda 6, 4i - Manual
Weird....
maple_leaf
Member
- :
- Mazda 6, 4i - Manual
What year's yours? 06?
Any update ?