Possible 6MT mechanical overrev mistake!!

[Seattle S65B40]

Here's the thread where i first described this issue, and no one responded.

http://www.m3post.com/forums/showthread.php?t=485535

I hope to talk with a tech or someone who really knows this engine and can tell me exactly when that happens and why. Maybe it should not be happening and in I need to take her in??

[KGB7]

Originally Posted by Seattle S65B40

That's interesting. I can't believe no one so far has seen that. I may have to start a whole nother thread on that to get more peoples eyes on this question and see what I can come up with. It's bizarre and has rarely happened, but the fact that no one else has seen it is concerning. I guess I'm not too worried, as the car has driven just fine after each time it happened. But what does it mean??

It means, that if you did any damage to the engine, the damage would be noticeable right of the back.

Unless you know for a fact that you did over rev to +9k, then you shouldn't worry about it.

The only way you would know 100% if there is any kind of damage to the engine, is by taking engine apart piece by piece and inspecting every internal component.

Im very confident that BMW engineers have foreseen every possible scenario even like yours, so they designed their engine from blowing up in such scenario.


I wouldnt worry about it for the time being, keep driving as you usually would, but in the mean time just keep your eye on it for a week or so. If there was any damage, it will shortly reveal it self.

[OC3]

Originally Posted by Seattle S65B40

Here's the thread where i first described this issue, and no one responded.

http://www.m3post.com/forums/showthread.php?t=485535

I hope to talk with a tech or someone who really knows this engine and can tell me exactly when that happens and why. Maybe it should not be happening and in I need to take her in??

When the OP (of thread 485535) says the 'car jerked at bit' because he forgot to shift & it hit the rev limiter, that's just fuel cuttin' off & the car suddenly slowing down.

I bet these engines can easily rev to 9,000 rpm (but, obviously wouldn't last as long).

Edit: oh, I guess you're referring to post #36 on that thread. Ask him to confirm again.

[alpina527]

Is the car still in warranty?

You can scan the max revs with Ediabas software. You should be able to find someone local who can plug it in.

If it reads over 8,400 it might be wise to see if you can find someone who can flash or edit the ecu before approaching a dealer.

Even if you don't have any problems it would reassure you knowing it's not gone over 8,400

[Seattle S65B40]

Originally Posted by alpina527

Is the car still in warranty?

You can scan the max revs with Ediabas software. You should be able to find someone local who can plug it in.

If it reads over 8,400 it might be wise to see if you can find someone who can flash or edit the ecu before approaching a dealer.

Even if you don't have any problems it would reassure you knowing it's not gone over 8,400

Great info. Thanks! Anyone local in Seattle wanna help me out???

[alpina527]

Originally Posted by Seattle S65B40

Great info. Thanks! Anyone local in Seattle wanna help me out???

If you search for one of the guys who does coding, they will probably be using this software

[cmk227]

Op don't worry. I took my car on a track day with buddies and we were redlining it in 2nd as we encounter some of the track turns. The car handle like a champ. I honestly worried a bit but she just a trooper. If you have no oil level missing nor any knocking noise you are fine.

The car can handle it. It was only third to second. Not 6th to 2nd. Don't stress.

[elp_jc]

Originally Posted by alpina527

You can scan the max revs with Ediabas software.

Has anybody here has actually seen the max revs pop up in any scan on a 6MT??? I asked TWO (selling and servicing) dealers; one initially agreed, but couldn't do it. Even called somebody and said it couldn't be done on the 6MT. Second flat out said it couldn't be done, that only if you had an accident a court order could get the last 5 seconds of data. I know for a fact you can only get max revs on Ferraris with F1, since it's stored on the tranny's ECU. Could it be the same with DCT??? I've never read in the 2 years I've owned my car of a 6MT owner who can get that information. I'd like to be proven wrong, how it's done, and what other information you actually get (like actual max revs -instead of 'overrev'-, date, mileage, engine temp, etc).

And what the hell is 'Ediabas software'? You need the hardware too to connect to the plug.

[Seattle S65B40]

Originally Posted by cmk227

Op don't worry. I took my car on a track day with buddies and we were redlining it in 2nd as we encounter some of the track turns. The car handle like a champ. I honestly worried a bit but she just a trooper. If you have no oil level missing nor any knocking noise you are fine.

The car can handle it. It was only third to second. Not 6th to 2nd. Don't stress.

Thanks! I feel fine about it today. I was pretty worried after it first happened. but the car drove great today and there are no unusual sounds. It can definitely take it like a champ. Same thing with E46 M3 too. That's where I picked up all my bad habits! If I drive anything other than an M car or P car after this, the thing will break on me so fast!

[Seattle S65B40]

Originally Posted by elp_jc

Has anybody here has actually seen the max revs pop up in any scan on a 6MT??? I asked TWO (selling and servicing) dealers; one initially agreed, but couldn't do it. Even called somebody and said it couldn't be done on the 6MT. Second flat out said it couldn't be done, that only if you had an accident a court order could get the last 5 seconds of data. I know for a fact you can only get max revs on Ferraris with F1, since it's stored on the tranny's ECU. Could it be the same with DCT??? I've never read in the 2 years I've owned my car of a 6MT owner who can get that information. I'd like to be proven wrong, how it's done, and what information you actually get (like date, mileage, engine temp, etc). And what the hell is 'Ediabas software'? You need the hardware too to connect to the plug.

I'm pretty sure the dealer can do this. It's been discussed before. Unless you're asking whether the actual RPMs reached are ascertainable, in which case, I don't know. It may just say that RPMs over 8400 were reached...

[Radiation Joe]

The ECU stores maximum rpm. Anyone that tells you otherwise is misinformed. Any dealer can pull up the info.

BTW, this wouldn't happen with a DCT.

[Seattle S65B40]

Originally Posted by Radiation Joe

The ECU stores maximum rpm. Anyone that tells you otherwise is misinformed. Any dealer can pull up the info.

BTW, this wouldn't happen with a DCT.

Haha. Get ready!

Well, "this" didn't end up being a problem, so if you mean a ridiculously rad downshift consummated by my own hands and feet? Then you're right, that won't happen on a DCT car...

[alpina527]

Originally Posted by elp_jc

Has anybody here has actually seen the max revs pop up in any scan on a 6MT??? I asked TWO (selling and servicing) dealers; one initially agreed, but couldn't do it. Even called somebody and said it couldn't be done on the 6MT. Second flat out said it couldn't be done, that only if you had an accident a court order could get the last 5 seconds of data. I know for a fact you can only get max revs on Ferraris with F1, since it's stored on the tranny's ECU. Could it be the same with DCT??? I've never read in the 2 years I've owned my car of a 6MT owner who can get that information. I'd like to be proven wrong, how it's done, and what other information you actually get (like actual max revs -instead of 'overrev'-, date, mileage, engine temp, etc).

And what the hell is 'Ediabas software'? You need the hardware too to connect to the plug.

I have seen it on my DCT. I can't see that a 6MT will be any different. It's all logged in the MSS60 engine ecu.

[elp_jc]

Originally Posted by Seattle S65B40

I'm pretty sure the dealer can do this.

I was too. I want proof . At least somebody saying he SAW a printout, a monitor, or something. Hasn't happened in 2 years.

Originally Posted by Radiation Joe

The ECU stores maximum rpm. Anyone that tells you otherwise is misinformed. Any dealer can pull up the info.
BTW, this wouldn't happen with a DCT.

Again, PROOF . Have you seen it??? What info is shown? Everybody says it can be done, and nobody has seen crap. I was told by a very large dealer and a medium one it couldn't be done. The large dealer thought it could, but when my car was connected, nothing popped up (the option was there, and that's when tech called somebody regional), hence my skepticism.

And we're talking maximum revs from the ECU (or DME in BMW parlance), whether over the limit or not, so I'm sure it'd show on DCTs too . But yes, we all know DCTs 'nanny' doesn't allow you to overrev .

[alpina527]

Originally Posted by elp_jc

I was too. I want proof . At least somebody saying he SAW a printout, a monitor, or something. Hasn't happened in 2 years.


Again, PROOF . Have you seen it??? What info is shown? Everybody says it can be done, and nobody has seen crap. I was told by a very large dealer and a medium one it couldn't be done. The large dealer thought it could, but when my car was connected, nothing popped up (the option was there, and that's when tech called somebody regional), hence my skepticism.

And we're talking maximum revs from the ECU (or DME in BMW parlance), whether over the limit or not, so I'm sure it'd show on DCTs too . But yes, we all know DCTs 'nanny' doesn't allow you to overrev .

It can definitely be done. It also tells you the maximum speed the car has ever been taken to and much more. No idea how to edit the info though

(My old SMG e46 M3 logged 8,360rpm)

I think Mike@powerchip might be able to suggest someone in your area.

[elp_jc]

Originally Posted by alpina527

It can definitely be done (My old SMG e46 M3 logged 8,360rpm)

I'm talking about a 6MT buddy . As I said earlier, automated trannies have a separate ECU, and that's what apparently has the capability of storing that information. That's the case with Ferrari. I want to hear from a 6MT E9x OWNER.

And no, I don't need that done now. I wanted that checked when I bought the car, since it had some miles on it, and wanted to make sure it wasn't revved not only over the max limit, but over the break-in limit.

[alpina527]

Originally Posted by elp_jc

I'm talking about a 6MT buddy . As I said earlier, automated trannies have a separate ECU, and that's what apparently has the capability of storing that information. That's the case with Ferrari. I want to hear from a 6MT E9x OWNER.

And no, I don't need that done now. I wanted that checked when I bought the car, since it had some miles on it, and wanted to make sure it wasn't revved not only over the max limit, but over the break-in limit.

I will see if I can plug into a friends 6mt and get back

[Raustin]

So...6MT cars don’t have a Rev Limiter? I'm not a BMW master mechanic but I do understand that limiters do limit the range of RPMs...unless they only work while under acceleration?

[KGB7]

Originally Posted by Raustin

So...6MT cars don’t have a Rev Limiter? I'm not a BMW master mechanic but I do understand that limiters do limit the range of RPMs...unless they only work while under acceleration?

Every car has a rev limiter controlled by a computer, even if the car is in Park or Neutral. But, any engine can be overeved with MT when you down shift one too many gears.

[Seattle S65B40]

Originally Posted by Raustin

So...6MT cars don’t have a Rev Limiter? I'm not a BMW master mechanic but I do understand that limiters do limit the range of RPMs...unless they only work while under acceleration?

Rev limiter can't save you from an overreving downshift. Only on acceleration can it save you.

[U235]

My first manual car was a 94 Integra GSR with an 8k redline. I was doing a 3-4 shift at basically redline and missed the gate and ended up in 7. Needle shot to 9.5-10k, I immediately clutched in. No issues, valves were the big concern. For peace of mind I did a valve adjustment the next day and nothing was out of spec. Drove the car for another 15k miles with no issues, then it was stolen.

Every engine is different though but mechanically the tach should show roughly an accurate depiction. If it only went into the yellow, you're fine. At 70-75 and miss into second, the immediate mechanical slow down would bring the speed down more. I think the m3 is at 65 at redline in 2nd so you'd still only be marginally over redline after the natural slowdown from all the mechanical resistance. I'd be surprised if you had any damage short or long term.

Cheers

[U235]

Originally Posted by KGB7

Every car has a rev limiter controlled by a computer, even if the car is in Park or Neutral. But, any engine can be overeved with MT when you down shift one too many gears.

Rev limiter is just a fuel cutoff, it can't prevent the mechanical inertia of the wheel speed to gear speed.