MazdaSpeed 2.3L DISI Turbo Blown Engine Resource Thread

[mouse0330]

Originally Posted by fbpem1 its fan fucking tastic.

+1 lol

[Betelgeuse]

Originally Posted by FORZDA 1 If you check the OEM specs, the stock motor makes max torque at ~3k rpm, so that is the point of max load on the engine, not at redline where the torque load has dropped considerably.

The question is, at part throttle/low boost, how much torque is being generated at around 3k rpms? I bet it's no where near the 280 ft/lbs. It's probably well under 200 ft/lbs. Does anybody have a dyno showing boost? Just cruising around I'm in vacuum most times.

Also somebody mentioned the cx7s before. With their automatics hunting for the highest gear possible at a given speed, they're probably loading their engines a whole lot more than we are. Yet they're aren't suffering from tons of blown engines. Also they are a good bit heavier which puts even more strain on the engine.

[badams118]

Well, CX7s have a different turbo, and are not being modded like ours are.

[lidokrantz]

till DCR, Haltech, Cobb, CP=E. etc etc give us a real definitive answer to why these moded engines are having issues than it makes sense to me to drive in balance...by that i mean enjoy the car in all rpms up to 6000 and at all throttle positions, but have common sense...the guy that's boosting at 18=23psi and running 320whp fully bolted car who is running WOT on a daily basis on most drives is pushing the common sense a bit....on the open/closed loop issue, IMO it's best just to boost thruu it at a reasonable throttle position and shift....my car feels good shifting at 4000-5000 rpms with the HKS BOV so i frequent that zone quite a bit...the turbo is not taxed, and it's not over -boosting.....and again downshift to acclerate if you want any pull, if not lay back and drive in vacuum for gas mileage... Lugging taxes the engine and is bad...especially with turbo cars like this one. This may be all voooodu as some have mentioned, as many high hp cars have not blown...Woosh, Laloosh. Tizi, etc, etc, but many have so i would side on the conservative side on this one till......and i am not a conservative person on life.....just trying to do the things that i have learned and makes sense to me...so far it's worked, my car runs friggin great and is still exciting to me 28 months later.....

[Superstretch18]

Originally Posted by Betelgeuse ...Also somebody mentioned the cx7s before. With their automatics hunting for the highest gear possible at a given speed, they're probably loading their engines a whole lot more than we are. Yet they're aren't suffering from tons of blown engines. Also they are a good bit heavier which puts even more strain on the engine.

The torque converter is probably keeping CX-7's from seeing as much engine load as they would see doing the same on a manual. CX-7's aren't that much heavier than an MS6. Out of curiousity, what kind of loads do you guys see at WOT?

Originally Posted by badams118 Well, CX7s have a different turbo, and are not being modded like ours are.

I'm insulted...

[badams118]

Well, I stand corrected!

[mlassek]

ANY LAWYERS OUT THERE? we need to get a class action lawsuit going.
there is no good reason all these motors are blowing up at such a young age and low miles.
especially since mazda isnt standing behind their product and warranty.

[bf360]

Originally Posted by Betelgeuse The question is, at part throttle/low boost, how much torque is being generated at around 3k rpms? I bet it's no where near the 280 ft/lbs. It's probably well under 200 ft/lbs. Does anybody have a dyno showing boost? Just cruising around I'm in vacuum most times. Also somebody mentioned the cx7s before. With their automatics hunting for the highest gear possible at a given speed, they're probably loading their engines a whole lot more than we are. Yet they're aren't suffering from tons of blown engines. Also they are a good bit heavier which puts even more strain on the engine.

jesus guys how many times do i have to say it, im not saying your blowing your motor at 3000rpm because of load necessarily, its like this, say you only part throttle boost by accident, and boost 5psi, that doesnt sound like much but if the ecu stays in open loop and your boosting and running lean

[Betelgeuse]

Originally Posted by bf360 jesus guys how many times do i have to say it, im not saying your blowing your motor at 3000rpm because of load necessarily, its like this, say you only part throttle boost by accident, and boost 5psi, that doesnt sound like much but if the ecu stays in open loop and your boosting and running lean

Well if you noticed, I quoted someone else but anyway....


Again, without having an idea of how much torque is being produced during that lean period, it's just a wild guess. For example, at 5psi, let's say the engine is making 180 ft/lbs (doubtful) and hits a lean spike to 250ft/lbs, that's still less than the max the motor is capable of. Realistically, it's not going to be that high. Now as the rpms rise, this becomes more and more dangerous.

[Betelgeuse]

Originally Posted by Superstretch18 The torque converter is probably keeping CX-7's from seeing as much engine load as they would see doing the same on a manual. CX-7's aren't that much heavier than an MS6. Out of curiousity, what kind of loads do you guys see at WOT?

I'm not sure what cx7s dyno at but it's likely the torque converter will sap some power but not a crazy amount. As for weight, they're close to 4000 lbs with AWD. That's almost 900lbs heavier than the ms3.

[Superstretch18]

Originally Posted by Betelgeuse I'm not sure what cx7s dyno at but it's likely the torque converter will sap some power but not a crazy amount. As for weight, they're close to 4000 lbs with AWD. That's almost 900lbs heavier than the ms3.

They dyno about 170 whp/200 wtq stock. Honestly, with everything I've done so far, I'm lucky if I'm over 225 whp. I refuse to dyno though...

Yeah, weight AWD CX-7 vs. MS3 is no comparison...

[phantom6294]

Originally Posted by bf360 theres no bermuda triangle lmao its known that boosting around 3-4 the ecu has a tendency to stay in closed loop and run really lean which can easily blow a motor at only 5 psi

Originally Posted by cld12pk2go I think you mean open loop, but yes this is the issue. I am ~13.5:1 in open loop under boost and quickly drop to ~11-12:1 in closed loop.

No, bf360 had it right... well, partially. Closed Loop is normal driving mode using the O2 sensor for AFR feedback, and Open Loop is conditions where the ECU relies on its tables only with no O2 feedback. The car does seem to have rather lean Commanded AFRs while in Closed Loop and under boost. To me, I really don't give two shits in which mode my ECU is operating. What I care about is Commanded AFR. An ECU could easily run in Closed Loop all the time and just have much richer AFRs for conditions that warrant rich(er) AFRs.

Any ways... 3-4 PSI... shit, that's weak!!! ;-) Try 15 PSI and a Commanded AFR of 12.6:1 while still in Closed Loop. YES... I mean Closed Loop. Or, how about 5.95 PSI with a Commanded AFR of 14.0:1??? Want more? Take a look at my attached pictures.

[DaleNixon]

Originally Posted by badams118 Well, CX7s have a different turbo, and are not being modded like ours are.

What turbo do they run?

[Lex]

As long as you are meeting the AFR targets I don't see a problem

[kwsmithphoto]

Informative thread, thanks everybody! Sounds like I should get at least a good boost gauge, any recommendations?

FWIW, I have a 2009. It has never knocked or pinged at all, not even in lugging conditions or WOT driving. I also get bad city mileage, which says something about how I drive it - not like a wimp.

I've learned to row the six speed and keep it between 3500 and 6000rpm. Not good for mileage but it's smooth and safe and fast... and it keeps me pretty busy.

Oh the freeway though, traffic usually limits me to about 65 which is roughly 3K in 6th gear, but I always drop a gear (or two) for passing.

I was reading Road and Track's long term test, which was still running fine at 40K. They had the usual 2007 problems but were happy with the fixes provided, and never had another problem with the engine. Then Mazdaspeed gave them a bunch of parts, including a CAI, and they ran it to 50K without blowing the motor.

No doubt it was a favorite of younger staffers and interns, but also got driven by their older, more conservative drivers, who probably drove it like any other car. Their long term fuel burn was better than I ever get, but I'm guessing it includes a lot more open road highway driving than I do.

Anyway, point being, they have a wide variety of drivers driving it differently for various reasons (road, and track) and it never throw a rod through the block. Good for them, I'm just saying that it's another data point to consider, and a pretty good one at that.

It's good to notice a pattern though, and y'all did a pretty good job. The lesson I'm taking from this is that cruising for MPG on level ground at low revs is OK, just downshift at least one gear if you want to do anything differently, and work the motor in a pretty narrow rev range when you wanna go fast.

Which I do, I just have to shift a lot more than I'm used to, and it burns a lot of fuel. Given the soot that collects on the exhaust tip, my shitty MPG, and total lack of pinging or knock, I don't need a monitor to tell me that it runs pretty rich in stock tune. If it has any lean spots I haven't found them yet, and I've never heard so much as a minor ping, running 91 octane, 10% ethanol CA gas since it was new.

[cld12pk2go]

Originally Posted by phantom6294 No, bf360 had it right... well, partially. Closed Loop is normal driving mode using the O2 sensor for AFR feedback, and Open Loop is conditions where the ECU relies on its tables only with no O2 feedback. The car does seem to have rather lean Commanded AFRs while in Closed Loop and under boost. To me, I really don't give two shits in which mode my ECU is operating. What I care about is Commanded AFR. An ECU could easily run in Closed Loop all the time and just have much richer AFRs for conditions that warrant rich(er) AFRs. Any ways... 3-4 PSI... shit, that's weak!!! ;-) Try 15 PSI and a Commanded AFR of 12.6:1 while still in Closed Loop. YES... I mean Closed Loop. Or, how about 5.95 PSI with a Commanded AFR of 14.0:1??? Want more? Take a look at my attached pictures.

Doah! I just reviewed my logs and you are correct.

This is the DashHawk code translation in the bottom right corner of the display:
Fuel System Status (C = Closed Loop, O = Open Loop, L = Open Loop due to Engine Load, F = Open Loop due to a Failure/Trouble
Code, P = Closed Loop with Problems, - = Data not available, U = unknown status)


When this value is displayed on the screen or on the PC from a data log, the following values are used:
0 = Unknown
1 = Open Loop
2 = Closed Loop
4 = Open Loop due to Engine Load
8 = Open Loop with Fault
16 = Closed Loop with Fault


I am typically in 2 until 3000-4000 RPMs, which is closed loop (usually with a ~13:1 AFR), then go to 4, which is Open loop due to engine load and my AFRs usually drop to ~11:1.

I just don't understand why our car aims for ~13:1 under 10+ PSI of boost after reaching full boost...

I understand running lean with retarded timing during spool up, which pumps a lot of heat into the turbine to accelerate the spool up time; however, I would feel much better if the AFR was < 12:1 under heavy load.

[lidokrantz]

kwsmithphoto.....i totally agree dude, as i have read that story as well back a couple months ago....stock cars or slightly bolted cars on stock tunes, stock boost have been fine...as the Road and Track Mazda Speed3 test car revealed..Even Cobb's mule is still kicking, although having a in-house tuner and dyno for 1000 pulls is handy Also True=Boost is for sure not easy on his car.. It's alway's cars that have mods that somehow are not in total balance or putting out to much TQ or boost, with a questionable tune , which cuts the safe window down quite a bit...It seems like the car stock is tweaked pretty good from the factory in torque with not alot of play room for upgrades..as per internals giving out......definetly some room to improve, but when the combination puts pressure, load, extra boost, etc etc the combination of all this has the car running on parameters obviously it can't handle, and then......Something will be figured out, and the cat's trying to make this a better car doing all these upgrades are feeling it...I feel bad for anyone thats gone through this, but at this point they no what you are getting into. Ask any woman...she will tell you some things just take time for a good outcome. and if rushed can lead to a un-wanted pop, Doh!!!!.

[kwsmithphoto]

Well some stocker's have blown too, so there might have been (or still is) a tolerance issue with the con rods. But ya, I agree, in stock trim these motors are already pretty wound up from the factory. It's just a re-worked older engine, not a new one that was designed from the ground up for DI and turbocharging.

Heck, what do you get from a Mazdaspeed CAI, 25hp and 30lbs? That gets you to 288bhp and 330lbs. Not too shabby. Which works out to 125hp per liter, and 143lbs per liter, which is in the big leagues in terms of specific output. Personally, I'm gonna stop there and leave well enough alone!

[lidokrantz]

you could count the stockers that have failed on one hand, in fact i have not heard of more than 2. But anyway, i agree with you at this current time that less is more, but i have been running the CP-E CAI and TBE since 3/07...4 months after i bought my car...and let me tell ya, if i had to give those two minor mods up, i would probably trade it in...to me it has made a big difference...In performance and indeed sound, 40 hp probably... and i do believe the CP=E CAI or SRI is a better air intake than the MazdaSpeed...in fact the original Speed intake was pulled off the market early on because of issues...Also i TOTALLY agree that running 300+bhp and 320 TQ is not shabby....coming from a Honda SI, my test drive in the Speed3 was downright thrilling, reminded me of the STI in mid range power for 10 grand less...lastly folks HAVE to remember that this is a 22,000+ car and it was designed to give you what it was designed for.....i wish it had more, but it is what it is...and i am at peace with it as is.

[Betelgeuse]

Anybody wanting peace of mind with their mods (especially those with extensive bolt-ons and piggybacks)should go with stronger internals and be done with it imo. There just doesn't seem to be a lot of leeway in terms of rod strength. And the tuning seems to be very complicated which could easily lead to a boost spike or lean condition. Why play russian roulette?

[kwsmithphoto]

Mazdaspeed's first CAI was an AEM unit. It worked, but threw some CEL's so they pulled it from the market. Then AEM developed an airflow straightener, which stopped the CEL's, so Mazdaspeed recently put the new version back on the market with their name on it.

The reason I waited for the new Mazdaspeed version is to help avoid any warranty nightmares. It's also less noisy than the SRI because of the extra plumbing.

Exhaust, I'm leaving alone. From the look of things, the factory did a pretty nice job, unlike the intake, which appears to have been designed by, uh, well by Ford.

[skeeter149]

Originally Posted by kwsmithphoto Mazdaspeed's first CAI was an AEM unit. It worked, but threw some CEL's so they pulled it from the market. Then AEM developed an airflow straightener, which stopped the CEL's, so Mazdaspeed recently put the new version back on the market with their name on it. The reason I waited for the new Mazdaspeed version is to help avoid any warranty nightmares. It's also less noisy than the SRI because of the extra plumbing. Exhaust, I'm leaving alone. From the look of things, the factory did a pretty nice job, unlike the intake, which appears to have been designed by, uh, well by Ford.

good luck with that brother. mazda is the man at finding bs reasons to void warranty and sorry that intake wont save you.

[kwsmithphoto]

Maybe not, but it certainly helps. I've done battle with corporate zone reps before and know how to deal with them (being nice actually helps). Since it has a Mazda part # and label on it, and they market it, sell it, and install it as a for-profit accessory, virtually any judge in the state would back me up without hesitation. Lacking any signs of abuse, of course, or proof of track or competition use.

IOW, Mazda can't really say please, buy this part from us, but we aren't responsible if your engine blows as a result. Well they can try, but it's a losing argument in court. If they try to deny a claim they have to prove it was your fault. Adding one of their own parts, and lacking any other evidence that the car was used normally, you have a winning case if you handle it properly.

Zone reps are always the people who make the call on a major warranty job, not the dealer, and their inclination is always to say "no." But they can be motivated to change their mind, especially if you let them know you'll take it to court if necessary, and have a solid argument. Will they spend $5000 of lawyering to fight a $5000 case? Not likely, it's easier and cheaper for them to just fix the damn car, and the zone reps know that.

[steve0617]

So just, as a n00b to clarify, the stock MS3 driven like it was intended, should be fine. It when you start modding it that things start occuring and Mazda gets bitchy. Is that about correct?

[Darksun280]

Originally Posted by steve0617 So just, as a n00b to clarify, the stock MS3 driven like it was intended, should be fine. It when you start modding it that things start occuring and Mazda gets bitchy. Is that about correct?

No your toast either way.

[Betelgeuse]

Originally Posted by steve0617 So just, as a n00b to clarify, the stock MS3 driven like it was intended, should be fine. It when you start modding it that things start occuring and Mazda gets bitchy. Is that about correct?

Except for a few unlucky individuals who claimed to have blown their stock engines, you're pretty much correct.

[FCmaniac]

Don't the Cobb AP maps eliminate any lean conditions caused by the open/closed loop switch delay that the stock map has?

I'm not going to panic about this car... I still love it. The only thing these blown engine posts do is make me minimize mods to keep the car easily swappable in case of an issue... and I may trade it in right before the powertrain warranty is up.

[Lex]

The more reports come through, the more it seems like there is a manufacturing flaw with these cars. Some people rag on them and nothing lets go. Most that let go are at low load conditions.

[Lex]

KR under WOT has A LOT to do with the fuel used. Example, the 94 octane where I'm at is shit and knock like a mother. 91 Octane just over the border knocks a lot less.

[FreeFlyFreak]

Originally Posted by Lex KR under WOT has A LOT to do with the fuel used. Example, the 94 octane where I'm at is shit and knock like a mother. 91 Octane just over the border knocks a lot less.

I have noticed a difference with different gas too.

Im in cali. so highest grade is 91.
But I notice a difference between gas stations.
As close as I can tell so far, the ones with the ethanol sticker run much worse.

I have had the best luck with the gas from the 76 and picking a pump that has previously poured 91.

[Lex]

This car is very very sensitive to gas quality. Mazda has made the knock sensor sensitive enough so that it can deal with poor quality gas. Not ideal, but it can and does deal with it.

Like I said, some water injection will cure all that up. That or pulling 4-5 degrees of timing.

[kwsmithphoto]

Originally Posted by FreeFlyFreak I have noticed a difference with different gas too. Im in cali. so highest grade is 91. But I notice a difference between gas stations. As close as I can tell so far, the ones with the ethanol sticker run much worse. I have had the best luck with the gas from the 76 and picking a pump that has previously poured 91.

Last time I checked, all gasoline sold in CA has ethanol in it, about 6% on average, year-round. 10% by 2010. Some regions have to increase the amount of oxygenate (more ethanol) where CO is more of a problem in the SUMMER, as you can see on this chart:

Summertime Gasoline Use-By Dates

So, basically we're always using "winter" gas, except in the summer when it gets even more "winterized." Welcome to California. But wait, it gets even stranger:

All gasoline sold in CA must be refined in CA, using a tightly spec'd formulation. There are only 21 refineries owned by a handful of companies, many of whom aren't associated or owned by a particular brand. In fact, "76," the retail brand name for Unocal, was bought and fully absorbed by Chevron in 2005.

Sources for the gasoline stock are generally defined by the station's proximity to a particular refiner's distribution network. Basically, whatever makes the most sense logistically is what you'll get at the pump.*

For example, if you pull off I5 in the middle of northern nowhere and find 4 different stations on each corner, they almost certainly got their basic gas from exactly the same refinery; it doesn't make sense to run multiple pipelines and distribution centers to serve a low density population. In higher density areas, where the refineries are concentrated and the pipelines more "diverse," you're more likely to pump gas from a refinery owned by the same company.

*The only real differences in a given region between different brands of gasoline are the additive packages, which are added when it's pumped into the truck! The actual refiner, though, just isn't very important.

The additives they use, primarily detergent blends, are important differences though. But the basic formulation and octane content is identical. Personally, I just stick with any of the "Top Tier" brands (Top Tier Gasoline) available in my area, 76, Chevron, Shell, and Texaco, and don't notice any differences in how the car drives.

For more information, here's a handy pamphlet:

http://www.energy.ca.gov/2008publica...0-2008-008.PDF

Which has nothing to do with blown motors, sorry for the thread drift, just thought some of y'all might find it interesting.

[lidokrantz]

i no some folks feel running different gas in this car does not matter, but i think it does so i stick to 1 brand and have since day i Shell 93 octane. I have swithched on one tank and used Amoco 93 another fine product IMO...These would be the only 2 i would put in my car if i can help it...But Shell has been in 99.9% of my fill ups and i generally go to the same gas station......if anyone has ever bought a bad tank of gas...the car will feel it especially gas with water in it or 89 octane that was sold as 93....this is not a documented thing, just that this car is finicky and taking bad gas out of the equation can't hurt...Now my Honda CRV.....i put anything in that sucker and it does not matter.

[kwsmithphoto]

Oh ya, contaminated fuel changes everything! And there's no way to tell until it's too late. But it's one of the reasons why I try to use newer stations or, ones that have replaced their tanks recently.

That was the silver lining of the MTBE debacle here in CA - when it started showing up in ground water, the state started looking for the sources, and it mostly coming from leaky underground storage tanks at specific gas stations. So, even though they banned MTBE, they told the stations with leaky tanks to replace them or shut down. It's an ongoing process, but many independently owned stations are being forced out of business because they can't afford new tanks.

Selling 89 as 91 is illegal, and the corporate stations are careful not to do it. But it does happen by mistake, sometimes. And who knows what's in the tanks at some places, I've seen unbranded gas stations I wouldn't use to fill a lawnmower.

[ASIC_BSEE]

Just punch it only after slightly letting off the gas at 3500 rpms and all is good. Don't let off the gas between shifts or shift really fast. Keep the carbon deposits at bay with seafoam or comparable. Upgrade your fuel pump. Monitor your EGT's and don't race it if the EGTs get above 800. You'll should never pre-ignite in this case.

[DaleNixon]

Originally Posted by ASIC_BSEE Just punch it only after slightly letting off the gas at 3500 rpms and all is good. Don't let off the gas between shifts or shift really fast. Keep the carbon deposits at bay with seafoam or comparable. Upgrade your fuel pump. Monitor your EGT's and don't race it if the EGTs get above 800. You'll should never pre-ignite in this case.

Huh?

[ASIC_BSEE]

Originally Posted by DaleNixon Huh?

What part don't you understand?

[DaleNixon]

I highlighted it. I'll highlight it and italicize it and underline it!

[ASIC_BSEE]

Ah, cause between shifts the car temporarily goes closed loop if you shift slow. The faster I shift, the smoother the car accelerates. If I take too long to shift, I get a high AFR spike (stoic) between shifts.

[kwsmithphoto]

Originally Posted by ASIC_BSEE Just punch it only after slightly letting off the gas at 3500 rpms and all is good. Don't let off the gas between shifts or shift really fast. Keep the carbon deposits at bay with seafoam or comparable. Upgrade your fuel pump. Monitor your EGT's and don't race it if the EGTs get above 800. You'll should never pre-ignite in this case.

Are these engines so bad that they really need that much attention??

I don't think so. At least I hope not.

I can understand if a modified car with an aftermarket ECU flash or piggyback tosses a rod, but seriously, this is a production car from a reliable company. I'm not going to babysit it with with aftermarket gauges and extraordinary driving techniques.

I'm glad I have a 2009. Given my shitty gas mileage and sooty tailpipe, I'm guessing they're just dumping lots of fuel into the motor during closed loop city driving now, which is what I mostly do.