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Hello,

I am a new MP6 owner and had the recall done about two-weeks ago. The first week no power loss issues, then the last week it is having the same intermittent power loss issue. When i turn off the engine and re-start the power is back to normal. The best way I can describe the loss is when you go into the normal boost range, the car just holds back all the way to the redline. Its like I am only getting 60% of the power.

After the recall and when there is no bosst problems the car is WAY faster than it was when delivered. Will resetting the ECU cure this? Is there a new Flash after MP401E?

Any ideas, it sucks. I am a recovering RX-8 owner who had to do a buyback because of all the issues with my previous car, I cannot do this again MAZDA.
 

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What kind of gas are you running... put 93 or 94 in if you can. Run out a couple tanks and see what happens.
 

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how many miles have you driven since the reflash? the ECU needs to relearn the trims and tends to make the car sluggish while doing it.
 

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Both of the above comments are useful. If you've runn 2-3 tanks of gas thru since the reflash and you're using 92-94 octane, then you've got a problem. It seems likely to me that there's a continuum with these cars-some people have super sensitive knock sensors and get the power loss even after reflash, some have less sensitive parts and didn't have the problem before. The reflash doesn't address the underlying problem-more of a bandaid, and for your car not working. I wonder if they replaced the knock sensor if that'd help? Can it be replaced?
 

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I'm kidda going through this now, but happened after I installed the CAI. It DOES not feel strong like it did after the reflash 2 weeks ago.
I had the battery unpluged for approx 4-5 hours (installing CAI, had to stop... had to go to church and did errands after), not sure if that screwed up the reflash????
 

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Discussion Starter #6
Running 91 Octane gas (Las Vegas) is all you can get. There is no way for me to get higher octane gas. Also, high ambient temps 100 deg plus.
 

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i had mine flashed a couple of times. i still had problems after the third trip. i don't know what the dealer did differently the forth trip, but it worked. no problems now; it was quite frustrating.

i'd take it back for another flash & make sure they reset the ECU as well.
 

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i had mine flashed a couple of times. i still had problems after the third trip. i don't know what the dealer did differently the forth trip, but it worked. no problems now; it was quite frustrating.

i'd take it back for another flash & make sure they reset the ECU as well.
[/b]

Thanks for the advice. I think I will. It is frustrating. The thing goes like hell when its running correct.
 

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Thanks for the advice. I think I will. It is frustrating. The thing goes like hell when its running correct.
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How do you reset the ECU? What does it do to the car?

Thanks
 

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disconnecting the battery for a few minutes will reset the fuel trims in the ECU. my car actually ran much worse after the reflash, and eventually the car threw a CEL. the car was in the shop for a whole day. the dealer cleared the code, reflashed & reset the ECU. it took about 200 miles for the car to run really well.

i've got an early build, 09/05, and had lots of problems with powerloss. i'm now running like it was supposed to all along.
 

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How do you reset the ECU? What does it do to the car?

Thanks
[/b]
Just to help clarify, here's a quick explanation of the difference between a firmware "flash" vs disconnecting the battery and 'resetting" the ECU:

1. Firmware flash: Firmware in our car is like the Operating System (ie. Windows 2000, XP Pro, Linux, MacOS, etc) in a computer. It's computer code that determines almost everything regarding the operation and behaviour of the car. A new "flash" is an upgrade of the code to fix certain issues and bugs, similar to the updates that MircoSoft releases constantly to fix Windows. Firmware is stored in special memory (usually called NVRAM, for non-volatile random access memory) that is not lost when power is cut. If it did, we'd have to reload the firmware everytime the battery was reconnected. However, this memory can be written over with new code, which is what the "flash" updates are actually doing.

2. "Resetting" the ECU: this is actually a misnomer. What is actually happening is the vehicle specific parameters are lost, causing a fall back to conservative default parameters. The way each car operates is unique, due to production variations, driver habits, environmental conditions (type and quality of gas, regional emissions regulations, etc). This uniqueness is captured as vehicle specific parameters, such as how much air is getting into the system, and how cool or hot it is (CAI), timing advance before knock sets in (affected by gas octane), etc. These parameters, unique to each vehicle, are "learned" by the ECU (which is programmed by the firmware) and stored in local memory. This local memory is not of the NVRAM variety, and requires constant (but minimal) power to be maintained. If the battery is disconnected, these vehicle unique parameters are lost. When the battery is reconnected, the ECU powers up and seeing no vehicle specific parameters, loads a set of default parameters that are quite conservative (better to be cautious than risk damaging the engine). After a bit of driving, the ECU will cautiously extend the limits (ie. allow more timing advance, etc) and "re-learns" new vehicle specific parameters which it keeps in memory.

Disconnecting the battery when installing a new part, such as a CAI, forces the ECU to start from the conservative default values, rather than re-using the old values stored from the stock airbox setup. This may be beneficial because the firmware may have a function where it says, if default values are being loaded due to powerloss, then something must have happened so speed up the learning process, whereas not disconnecting the battery may result in the ECU taking longer to relearn the new parameters to work with the improved flow. The ECU will eventually learn this, but possibly not as quickly.

Hope this helps.
 

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Discussion Starter #14
Just to help clarify, here's a quick explanation of the difference between a firmware "flash" vs disconnecting the battery and 'resetting" the ECU:

1. Firmware flash: Firmware in our car is like the Operating System (ie. Windows 2000, XP Pro, Linux, MacOS, etc) in a computer. It's computer code that determines almost everything regarding the operation and behaviour of the car. A new "flash" is an upgrade of the code to fix certain issues and bugs, similar to the updates that MircoSoft releases constantly to fix Windows. Firmware is stored in special memory (usually called NVRAM, for non-volatile random access memory) that is not lost when power is cut. If it did, we'd have to reload the firmware everytime the battery was reconnected. However, this memory can be written over with new code, which is what the "flash" updates are actually doing.

2. "Resetting" the ECU: this is actually a misnomer. What is actually happening is the vehicle specific parameters are lost, causing a fall back to conservative default parameters. The way each car operates is unique, due to production variations, driver habits, environmental conditions (type and quality of gas, regional emissions regulations, etc). This uniqueness is captured as vehicle specific parameters, such as how much air is getting into the system, and how cool or hot it is (CAI), timing advance before knock sets in (affected by gas octane), etc. These parameters, unique to each vehicle, are "learned" by the ECU (which is programmed by the firmware) and stored in local memory. This local memory is not of the NVRAM variety, and requires constant (but minimal) power to be maintained. If the battery is disconnected, these vehicle unique parameters are lost. When the battery is reconnected, the ECU powers up and seeing no vehicle specific parameters, loads a set of default parameters that are quite conservative (better to be cautious than risk damaging the engine). After a bit of driving, the ECU will cautiously extend the limits (ie. allow more timing advance, etc) and "re-learns" new vehicle specific parameters which it keeps in memory.

Disconnecting the battery when installing a new part, such as a CAI, forces the ECU to start from the conservative default values, rather than re-using the old values stored from the stock airbox setup. This may be beneficial because the firmware may have a function where it says, if default values are being loaded due to powerloss, then something must have happened so speed up the learning process, whereas not disconnecting the battery may result in the ECU taking longer to relearn the new parameters to work with the improved flow. The ECU will eventually learn this, but possibly not as quickly.

Hope this helps.

This really helps out. You seem VERY knowlegable. So basically, the ECU reset may help, but more than likely I have another issue or the firmware does. I dont think the high ambient temps in Las Vegas are good for Mazda cars. My RX8 had to have a new engine and now this. I really hope they can pinpoint this issue.

I went through a year of issues with my 8 before pulling the trigger and doing a buyback.
[/b]
 

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As your nick implies, are you from UK? If so, I am surprise you experienced such a bad powerloss as your and our car is both less HP rated. I thought for this reason we don't experience as much powerloss as most US or NA MPS 6 owners. ATleast that is the case here DownUnder.
 

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2. "Resetting" the ECU:
After a bit of driving, the ECU will cautiously extend the limits (ie. allow more timing advance, etc) and "re-learns" new vehicle specific parameters which it keeps in memory.

Disconnecting the battery when installing a new part, such as a CAI, forces the ECU to start from the conservative default values, rather than re-using the old values stored from the stock airbox setup.
[/b]
So... how long or how many miles do we have to drive before the ECU loads in a more aggressive value???
 

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the car is constantly "learning" as soon as you start driving, the longer you drive the more accurate your fuel trims will be (assuming the weather stays the same for a good time). It doesn't really ever load a more aggressive value, just pulls or adds more fuel and timing depending on everything that happened in the past. Obviously your car can't read the future but it does a best guess type of fuzzy logic based on all the past driving you've done.
 

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Sorry if this might sound stupid, but... I assume the reflash that was completed won't get deleted by disconnecting the battery??
 

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Sorry if this might sound stupid, but... I assume the reflash that was completed won't get deleted by disconnecting the battery??
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Correct, the reflash is software based...everytime you startup the car, it boots this program which cannot be deleted by disconnecting the battery.
 
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