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Discussion Starter #1
This information straight from a Mazda QMD Service Manager freshly back from the national QMD meeting.

What is happening when the power loss occurs?
When the Mazdaspeed 6 detects 1 knock, it cuts the electronic throttle input to 33%. That means if you have the pedal floored completely down, the max the PCM/ECU allows the throttle plate to open is 1/3. Since the throttle is electric, the PCM can completely override any and all driver inputs for the safety of the engine. Those who ever owned a 6 with a bad maf sensor know exactly how this works.

What is knock?
Knock, or pinging/denonation, is when the unburned fuel/air mixture in the cylinder combusts prior to the flame front (of the actual combustion process) completes. This causes an interruption in combustion due to the two shockwaves intersecting and generally results in a metallic "ping" sound.

Why is this occuring the MPS 6?
The main problem seems to stem from the lack of pure 93 octane gas in many areas of the United States. In Japan, 93 octane gas is available in all areas, but this is not the gas in the United States. Higher octane gasolines reduce the chance of premature detonation by increasing the activation energy required for combustion. (Simple explanation). This help prevents a mixture of air/fuel from detonating prior to the flame front (from the spark).

Other causes of detonation involve excessive combustion temperatures, (which can be related to cooling issues with either the air charge or the coolant system), timing advanced too far, and running too hot a sparkplug.

What is Mazda doing about this?
Mazda is adjusting the # of cycles it takes the knock sensor to throw the car into 33% throttle mode through a PCM/ECU reflash. The sensitivity is also going to be addressed, but not significantly, as the knock sensor is still there to stop detonation from occuring. The cycles should greatly reduce the # of occurances from owners. This flash is "supposed" to be available next month, but mazda is well known for "guessing" at when a particular fix will be available to the dealerships.

What can you do in the meantime?
1) Run 93 or 94 octane gas.
2) Move to northern canada
3) Shift earlier (within the powerband) instead of taking the car to redline. When a turbo is in its most efficent range, it produces LESS heat then when its out of this range. Exhaust temps will most likely be reduced if you shift in the 5.5-6.0k range, then trying to pull to 6700 rpm. Lower exhaust temps translate into lower combustion temps. Lower combustion temps = less chance of detonation.
4) Increase the water concentration in the cooling system (only in warmer climates). Swapping to a 60/40 or 70/30 distilled water/coolant mix will increase cooling efficency of the turbo, engine, transfer case, and oil.

There were also a number of other MPS 6 issues mentioned, including purge solinoid problems, coolant resevoir hose blow offs, and some really odd cel code that nobody here has ever mentioned.

I'm put this information up as a CRP on 6tech until the flash is released in case anyone wants an easy uncluttered link.
http://forum.mazda6tech.com/viewtopic.php?p=43280#43280
 

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Excellent writeup. Luckily I don't have powerloss issues, but I do have the other things you mentioned. I already had the purge valve replaced and I noticed some dried coolant splashes this morning doing an install, glad to know it's just the resevoir.

Cam
 

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if someone with a consistant loss problem could try something for me. in the 6i section there is a "free mod" that i posted about advancing timing a bit. well in my car, i use it the opposite way and retard my timing by 4* (or so) where i experience knock at stock setting. this is 10 minute mod, and it could be just enough to stop the issue? given this might pull a couple hp out as well, but it might lead to a consistant power, rahter than on/off.

if there are questions hit me up. this is a band-aid, not a fix.
 

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Discussion Starter #4
Cam,

The purge issue is exactly the same one as the standard 2.3's. So look for threads discussing that in the 2.3 forums for more information. Basically with that issue, mazda changing the purge solinoid (I can't spell that ever) after 04, and the new model sucks ass.

The coolant line is due to mazda using a slightly too large hose between the resevior and whatever the hell its connecting too. The fix (TSB and MRI not out yet) is just replacing the hose with a smaller diameter one.
 

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Hmmm, I wonder if the weird CEL was what I had when I had 2 mysterious CELs pop up and they didn't really know what was wrong. They replaced a couple of back pressure (?) tubes and check valves, and somehow it's fixed.
 

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Other causes of detonation involve excessive combustion temperatures, (which can be related to cooling issues with either the air charge or the coolant system), timing advanced too far, and running too hot a sparkplug. [/b]
given that one or more of these things may be causing detonation, in addition to differing grades of gas in the U.S., in your opinion is the reflash going to be enough to fix this issue and to protect the engine?
 

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Thanks Crossbow now that is a definitive to what is happening when Powerloss occurs. With the thottle blade only opening part of the way that explains also why some people do not see the full boost on their gauges when they experience the loss of power. Now use your connections and see if they will allow ECM code/module sharing (similiar to what Ford did) with the aftermarket tuners so we can start tuning these things on the Dyno.
 

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Discussion Starter #8
turbomatt,

I think we'd be happy if Mazda just started telling everyone what changes they make every pcm/ecu reflash. We've only got them to the point where they say "oh this is for p0069 cel's"...not to the point where they say..

"We reduced timing when the coolant is between blah and blah degree's, as well as richening the fuel mixture at 5,000 rpm in open loop, the percentage of egr purging has also been adjusted"

It's pretty aggravating, both for the aftermarket, and the dealerships, when mazda doesn't even give anyone a slight clue as to what's been changed. There are all sorts of hidden little changes each pcm/ecu reflash...like the cut off for the A/C changing for the rx8, even though that was never listed as a fix.

Bandit, I hope so. I don't know the "exact specific changes" just exactly what I've told you.
 

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Excellent. Thank you Crossbow.

Now, I wonder if I should pass this along to my local service dept. manager. I was never able to get the car to them when it happened. I should drain the tank and fill up with some no additive gas when I leave this 'e-check' county :-(

Jason
 

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(another way of asking) is it feasible or even safe for mazda to scale back the ecu's reaction to the detonation without addressing the underlying cause(s) for the detonation? if they just de-sensitize the ecu, wouldn't that leave the car prone to engine damage? or should we expect the fix to address the cause as well (retard timing perhaps)?
 

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What's interesting is that pretty much all of us are seeing the "effect" and we have to restart the engine to clear it.

I never changed gas (was 93 oct) and the problem went away once I shut it down for the night. Until that point it went 10-12 miles with the problem.

It certainly feels like a starvation problem to me.

Now on to the throttle montior project to snoop what the computer is doing!!! :D
 

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If you have the ability to monitor..

Check throttle request vs TP actual as the car is in this mode.

IIRC the max "actual" is somewhere near 88% when the car is performing as it was designed.
 

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I run Water Wetter from Red Line.. and drained over 35% of the coolant. The only time I notice the auto pulling fans come on (radiator) is when I sit at idle for awhile on nice HOT days with the A/C running. Like today, it was 94 and we were running the air on low with the windows open. We still like fresh air :lol:
I have ran Red Line Wetter for years in my track car as I do not run ANY fan. and it has still yet to overheat.
 

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Discussion Starter #15
The fan's don't kick in till after timing retard has occured. First fan turn on is around 212F.

The only way around this is to modify the signal going to the fan controller as per the other fan mod threads in the 2.3 forum.

Basically if you ever hear your high speed fans engage (you'll know), the coolant is over 220F which is a good indicator that...

Your engine oil, transfer case oil, and turbo (well duh) oil is at LEAST 220F. The coolant in the MPS 6 has to do alot more work then in the i or s standard 6, yet its pretty much the exact same size as the normal L3 radiator.

So in other words...just because your fan's aren't on, doesn't mean that the car's coolant isn't over 210F...the water temp gauge is just a dummy gauge with a 60F deadzone. It won't move until the cooling system starts to fail.

The only way to see your "actual" water temp, is to install a real temp gauge, or hook a scanner up to the car or data logger.
 

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some good info u have come up with ,man very helpfull.
 

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Discussion Starter #17
It should be mentioned that the part that says "what you can do in the meantime" is my suggestions, not mazda's. Mazda's only suggestion was.."Run premium and wait for a fix". I figured people wouldn't be happy with just that answer, so I provided a few ideas for possibly reducing coolant and charge temps, both which reduce the chances for detonation, and thus reduce the chance of a knock event.
 

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It should be mentioned that the part that says "what you can do in the meantime" is my suggestions, not mazda's. Mazda's only suggestion was.."Run premium and wait for a fix". I figured people wouldn't be happy with just that answer, so I provided a few ideas for possibly reducing coolant and charge temps, both which reduce the chances for detonation, and thus reduce the chance of a knock eve

Any ideas help .
 

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i know after i put in the turbo my temps went much higher, though i didn't have a gauge pre-turbo to know what the dif was. i run a pretty standard 210 all the time now, i've seen in drop to 190-195 while hwy driving with cruise control, and i've seen it up to 230 while playing on city streets, stop and go. we'll see how much the AWR radiator helps with this part of things.

anyone try retarding the timing a bit to see if it does anything? just wondering for a bandaid fix?
 

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Still haven't had powerloss...

But anyways... Tea, do you think the AWR will fit on a speed??? I was really looking into a few days ago but decided to hold off as it might intrude on a FMIC...
 
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