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View Full Version : RPMs bogging down during hard acceleration, Help Plz!!



AzkotikBMW
09-07-2011, 09:46 AM
Ever since the weather got warm (aka got REALLY hot/humid 100*+) my car has been acting really weird, and it's really starting to worry me. The car drives like complete shit. Here's the problem:

If I start out at a stop, my acceleration is great up to about 6500-6800 RPM, until I shift into a higher gear. Once I shift, and put the pedal back to the floor the RPMs bog down about 500-1000 and then make it slowly back up to where it should be. It sounds to ME (no expert here) like the car is running WAY too rich, and causing it to bog down whenever its run hard. If you watch the link I put in the post you can see an example of me going hard from ~10 mph to 90mph. At about 15-18 seconds into the video you can see exactly what I am talking about.

Any insight into what may be wrong with my car would be much appreciated Mafia!:ninja
Thanks a ton in advance guys!

PS. Enjoy the sound of the car with the windows down :D I love it!!!



http://www.youtube.com/watch?v=njEsoXWOvjo

danewilson77
09-07-2011, 09:57 AM
Clutch maybe?

HTC Thunderbolt+TT

RITmusic2k
09-07-2011, 10:03 AM
I haven't seen the video yet, but if the problem was a slipping clutch I'd expect the revs to skyrocket and then settle, not dip and recover...

Johnmadd
09-07-2011, 10:21 AM
Clutch slipping, don't get on it like that until fixed.

wsmeyer
09-07-2011, 10:42 AM
Clutch slipping?

Really?

That means there's some sort of sensor in there to tell when the clutch disc should be locked and cuts engine power when it's slipping?

I don't know about that...

It's under hard load, then no load for a split second, then hard load again when it bogs. It does sound like a too-rich problem. I wonder if a leaking fuel injector could cause that.

William.

danewilson77
09-07-2011, 11:09 AM
Try to take off in 6th gear.

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AzkotikBMW
09-07-2011, 11:22 AM
Try to take off in 6th gear.

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I can never tell if you're being serious or not DW......but are you talking about the "if you can move at all from 6th gear" trick?

Johnmadd
09-07-2011, 11:56 AM
I think he's being serious. I had a clutch do that same thing before it went on me, it will progress.

llll1l1ll
09-07-2011, 01:08 PM
It sounds like your clutch is slipping like crazy.

danewilson77
09-07-2011, 01:34 PM
I can never tell if you're being serious or not DW......but are you talking about the "if you can move at all from 6th gear" trick?

Srsly

HTC Thunderbolt+TT

Hornung418
09-07-2011, 01:37 PM
Clutch fo sho!

wsmeyer
09-07-2011, 01:48 PM
Clutch slippage is when the pressure plate can not provide enough force to lock the disc to the flywheel and transfer the rotational force of the flywheel, which is attached to the engine, to the clutch disc that is attached to the transmission. When this happens the engine revs spike. Which is EXACTLY THE OPPOSITE of what he is experiencing.

William.

Hornung418
09-07-2011, 02:04 PM
So what's your expert opinion, Webster?

Either way his car is bogging down, which would make it clutch related if it revs fine when completely engaged and when disengaged.

Azkotik, go a head and clean your MAF just for shits and see if your problem is any better.

danewilson77
09-07-2011, 02:07 PM
So what's your expert opinion, Webster?

Either way his car is bogging down, which would make it clutch related if it revs fine when completely engaged and when disengaged.

Azkotik, go a head and clean your MAF just for shits and see if your problem is any better.

Or unplug It.

HTC Thunderbolt+TT

wsmeyer
09-07-2011, 02:39 PM
So what's your expert opinion, Webster?

Either way his car is bogging down, which would make it clutch related if it revs fine when completely engaged and when disengaged.

Azkotik, go a head and clean your MAF just for shits and see if your problem is any better.

I was trying to explain it as simple as possible so that you could understand it and realize on your own that his clutch is not slipping. Apparently I didn't do a very good job so we'll try this again.

Under acceleration, the clutch transfers torque from the engine to the transmission. Under de-acceleration, it transfers torque from the transmission to the engine. Under NO SITUATION* does it magically generate any force of it's own and therefore CANNOT cause an engine to bog down.

William.

* if your throwout bearing freezes it will generate a slight amount of friction but you would know if this happened as it would self destruct in a matter of seconds.

danewilson77
09-07-2011, 02:52 PM
Keep it civil. I'm out. Guess I don't understand.

HTC Thunderbolt+TT

az3579
09-07-2011, 05:08 PM
I would start by getting that check engine light code read.
It for sure sounds like there is some serious clutch slippage here, and I seriously doubt it's from driver error as it happens on every single shift, and I've never seen someone consistently do that. I actually don't see any power dipping going on, it just looks like the clutch is slipping to a point where it's not transferring that power correctly. A slipping clutch will not be transferring all the power the engine has to offer, which may very well result in decreased performance. Either way, if that's not driver error, I wouldn't drive it like that and would have the clutch inspected ASAP.

I did notice something that may seem like something the OP is doing wrong though; at 20 seconds, you see the revs rise right before falling back down again for a shift change. OP, did you have someone else drive your car and see if the problem is still evident for them? Are you sure it's not something you're doing wrong with the shifts? Every time I come back to think about it, the first thing I'm thinking is "slipping clutch". I'd be reeeeally curious as to what this is if that's not it, and am itching to learn something.

Oli77
09-07-2011, 05:16 PM
CDV deleted or not (could be that simple)?. But like wsmeyer, if clutch was slipping, RMP would go up fast.

az3579
09-07-2011, 05:32 PM
CDV deleted or not (could be that simple)?. But like wsmeyer, if clutch was slipping, RMP would go up fast.


So I'm confused; if it's not the clutch, why does it look like one is slipping the clutch while giving it throttle?
The only people I've seen do that are people just starting to drive a manual... I seriously doubt the OP is just learning how to drive a stick.

What other potential causes could there be to that particular behaviour? Because I'm not sitting in the car, I don't see any power bogging, only the behaviour of what looks like clutch slippage. Would you have any insight on this Oli?

Johnmadd
09-07-2011, 06:01 PM
The slip is the hi rev and the dip in rpms is when it engages fully, or as much as a worn clutch can. Think of doing a burnout and tires, the tires slip until they grab and as that happens the rpms go high until they grab then the rpms go lower. Make sense?

llll1l1ll
09-08-2011, 04:11 AM
CDV deleted or not (could be that simple)?

I was thinking about this yesterday. If the CDV slows down the speed of the clutch engagement, then no matter how quickly OP lifts his foot off the pedal, the clutch will just slowly engage with the flywheel, which could perhaps cause this "bogging" sensation. In my E30, I can just shift from 1st to 2nd and it'll chirp the tires if I'm quick. It would never slip like that.

It could also be a faulty piece of clutch equipment, like a pressure plate, fork, TOB, slave or master cylinder. I'm not a mechanic by any means - I'm just saying.

On a side note, if it is running rich, then the SES light is trying to tell you something!

VA//M3
09-08-2011, 06:03 AM
I'm surprised you didn't get a 2nd gear tire chirp followed with a slight kick sideways from the rear... Like on the new e90 M3's.

VA//M3
09-08-2011, 06:05 AM
I was thinking about this yesterday. If the CDV slows down the speed of the clutch engagement, then no matter how quickly OP lifts his foot off the pedal, the clutch will just slowly engage with the flywheel, which could perhaps cause this "bogging" sensation. In my E30, I can just shift from 1st to 2nd and it'll chirp the tires if I'm quick. It would never slip like that.

It could also be a faulty piece of clutch equipment, like a pressure plate, fork, TOB, slave or master cylinder. I'm not a mechanic by any means - I'm just saying.

On a side note, if it is running rich, then the SES light is trying to tell you something!


That's basically what happens. The CDV will never allow you to up shift properly like a manual car should be able to. It will actually slow your car down.

That's becuase your E30 is a proper manual car without a CDV valve.

Take the CDV valve out and you will be back in command instead of the car commanding you.

AzkotikBMW
09-08-2011, 06:06 AM
I had the SES codes checked about a month ago and the only code that was thrown is the O2 sensor failure from having my Ebay headers. BUT there could be new ones since then and I would never know because the light is always on.

I have not done the CDV delete, so that shouldn't be the issue.

I also have been driving this car for almost a year now, and have never had a problem like this until now, so I'm don't think its my lack of experience driving the car/manual trans that is causing this.

I've posted this on 3 different bimmer forums, and the first reaction from everyone (to my dismay) is that it's the clutch slipping. But there are a select few that swear on their life it can't be....so I'm getting a little confused :P

VA//M3
09-08-2011, 06:08 AM
I had the SES codes checked about a month ago and the only code that was thrown is the O2 sensor failure from having my Ebay headers. BUT there could be new ones since then and I would never know because the light is always on.

I have not done the CDV delete, so that shouldn't be the issue.

I also have been driving this car for almost a year now, and have never had a problem like this until now, so I'm don't think its my lack of experience driving the car/manual trans that is causing this.

I've posted this on 3 different bimmer forums, and the first reaction from everyone (to my dismay) is that it's the clutch slipping. But there are a select few that swear on their life it can't be....so I'm getting a little confused :P

I would take out the CDV valve if you know how to properly drive a manual. I test drove an 03' M3 which has a CDV valve and it was like I was back in my old car(pre CDV valve delete). Completely different clutch engagement everysingle time. I hated it.

OUr pressure plates are also self-adjusting. Your pressure plate might be stuck and not able to adjust itself again. When I first bought my car the clutch left a lot to be desired but after I drove it without the CDV properly it was much more consistant and more grippy.

I would take the CDV valve out and drive normal. As in pushing the clutch all the way in, shifting and engaging it smoothly right at where the revs match the gear. And also rev match downshift. and very little engine braking less (clutch slip braking) for less than 2 seconds and seeing if the clutch feel improves.

CDV valves are evil. They're like Traction control, and haldex differentials. They take the skill and fun out of driving.

Technically our cars do have LSD but it is a failing concept in the real world

EDL (often referred to as Electronic Traction Control.)
This system is used by most VW models today, many Audis and several other car models, and was first introduced for offroad use in the Mercedes ML320 (AWD) and is undoubtably used by many others today.
It's what I call the poor man's LSD

problem with the way EDL works is that it's pretty harsh. The pulsing of the ABS isn't progressive. If the ABS is on, it applies full braking power followed by zero braking power.. full, zero, full, zero.. The torque from the engine that's being transferred repeatedly all the way across the drivetrain from wheel to wheel a dozen times a second, puts stress on everything. Brakes, rotors, axles, U joints, output shafts, and the differential itself. The left and right halves of the differential in the VW 02A transmission are held together with rivets which if forced to take this pounding too long will eventually fail. Neat huh?

That is why the system is aweful during the snow. It's to crappy. Only reasonable solution.. take your foot off the gas and turn off DSC.

^^ that is why BMW deemed a traditional torsen, posi, or viscous LSD "unnecessary". They really just didn't want to spend an extra 1.5k in fitting a real LSD and used it as a cost cutting measure.

AzkotikBMW
09-08-2011, 07:06 AM
Thanks a lot VA!

VA//M3
09-08-2011, 07:16 AM
NP!

Also when rev-match downshifting--double clutch. When passing through nuetral take the clutch out to the biting point, blip the gas, and press the clutch back in and downshift. It may help knock some sense into the pressure plate.

telijah
09-08-2011, 07:17 AM
Quick and dumb question, but when you start your car, and the dash does it's light check, do you DSC lights come on at all? I am wondering if your shifting too hard, causing slight wheel slippage and thus the car bogging itself out as it usually would when the wheels are loosing traction... Seems like VA is talking along the same lines but your vid doesn't show the transaction light coming on.

AzkotikBMW
09-08-2011, 08:07 AM
Quick and dumb question, but when you start your car, and the dash does it's light check, do you DSC lights come on at all? I am wondering if your shifting too hard, causing slight wheel slippage and thus the car bogging itself out as it usually would when the wheels are loosing traction... Seems like VA is talking along the same lines but your vid doesn't show the transaction light coming on.

Yes, it does. It also comes on it I hit the DSC button on the dash.

telijah
09-08-2011, 08:38 AM
OK, and is not coming on when experiencing your problem, correct? :) I know, sorry if thats a dumb question and you're well aware of this. I would then check for a CDV. Did you say your car has always done this, or is this a new development?

Pooters
09-08-2011, 09:49 AM
Def clutch

wsmeyer
09-08-2011, 10:07 AM
I feel like I'm listening to people trying to convince someone the world is flat.

Anyone who thinks that a clutch slipping will cause engine rpm's to drop clearly has no idea what they are talking about.

William.

danewilson77
09-08-2011, 10:11 AM
I feel like I'm listening to people trying to convince someone the world is flat.

Anyone who thinks that a clutch slipping will cause engine rpm's to drop clearly has no idea what they are talking about.

William.

You're right.

Actually, this is kind of what my car was doing when the fuel pump went out. I wonder if checking fuel pressure at the fuel rail is warranted.

And FYI...the world is flat...it's just rolled around a magma core...hehe

Hornung418
09-08-2011, 10:23 AM
I feel like I'm listening to people trying to convince someone the world is flat.

Anyone who thinks that a clutch slipping will cause engine rpm's to drop clearly has no idea what they are talking about.

William.

Well instead of telling us that we're wrong, why don't you tell us what is happening in the video? Your arrogence is appalling regarding this situation. You know what it's not...but how does that better the OPs problem? It's not working for me and I can sense a little disdain from others.

No further questions, Your Honor.

RootedDROIDXstatus. Come at me, bro.

wsmeyer
09-08-2011, 10:49 AM
You're right.

Actually, this is kind of what my car was doing when the fuel pump went out. I wonder if checking fuel pressure at the fuel rail is warranted.

And FYI...the world is flat...it's just rolled around a magma core...hehe

Certainly a possibility. The problem with trying to diagnose engine problems is the symptom might be caused by the computer compensating for a completely different problem. Since he mentioned aftermarket headers I'll throw out a possibility. If he has an exhaust leak upstream of the O2 sensor when he lets off the gas it will cause a drop in exhaust pressure which could easily suck in some outside air making the computer think the engine is running lean, pump some more fuel in there to compensate and wala.. engine bog.

Kind of a stretch but probably the only thing I would look for before getting an error read out.

William.

bcleaver
09-08-2011, 10:56 AM
I don't know what it is, but I think it is still helpful to remove things it's not through the process of elimination. So to help the OP I think it's reasonable to let him make an informed decision about what to replace based on what it may or may not be.

I agree it is not the clutch slipping. Any non-engagement of the clutch either through the clutch being bad, or a faulty/slow CDV engagement would result in HIGHER rpm's between shifts, not lower. Anyone that has ever had a clutch go out on them can relate...you stomp the gas and your revs go up, but your car does not go any faster...the power transfer between the engine and the tranny doesn't exist, or is diminished so all that power just goes to spinning the flywheel.

It is also unlikely to be the traction control system, only in that he's getting it shifting into higher gears. The stock power from these cars isn't enough to cause rear tire slippage above 3rd gear in a straight line.

It's possible the ECU is pulling timing because it thinks it's running rich or lean because of the faulty o2 sensor or somthing. I would guess it's something along those lines, but really don't know.

Keep us posted though when you figure it out, and good luck.

Pooters
09-08-2011, 11:14 AM
I've replaced the clutch in my 240sx and Toyota Pickup because they were doing the same thing. Clutch not holding on at higher RPM's in between shifts and gradually grabbing. Once a clutch is almost all the way out it wouldn't bog down at all and instead go up in RPM's.

az3579
09-08-2011, 01:45 PM
It's possible the ECU is pulling timing because it thinks it's running rich or lean because of the faulty o2 sensor or somthing. I would guess it's something along those lines, but really don't know.

Keep us posted though when you figure it out, and good luck.

Regarding the headers, the OP mentioned he has eBay headers and a resulting O2 sensor code. While that code may have been on since he replaced the headers, it is possible that the O2 sensor has gone bad since then. He wouldn't know it though because he's used to the SES light being on. OP, have you read the codes after this started happening to see what's what? Has anything new other than the O2 sensors come up?

How many miles on the O2 sensor? They typically need to be replaced every 100k otherwise you may 1) get worse fuel mileage, 2) run too rich or lean, or 3) throw codes. In your case, 1, 2, or both may be possible. 3 you wouldn't know because you already have codes from the headers.

VA//M3
09-08-2011, 02:59 PM
OP, have you ever replaced your crank sensor?

kayger12
09-08-2011, 03:18 PM
I feel like I'm listening to people trying to convince someone the world is flat.

Anyone who thinks that a clutch slipping will cause engine rpm's to drop clearly has no idea what they are talking about.

William.

Please check your PMs.

Droid X. Tapatalk. Use it.

danewilson77
09-08-2011, 03:34 PM
Here is some stolen info.....for all of us. Just here to help.


Signs of a Clutch Going Bad in a Manual Car

By Annie Lee Tatum, eHow Contributor updated May 05, 2011


Know the signs of a slipping clutch.
Having a clutch replaced is a costly and labor-intensive proposition, involving separating the transmission from the engine. Driver and passenger safety is paramount; at the same time, it's best to be sure the clutch is really failing, or "slipping," before investing in expensive repair work and a replacement clutch. Fortunately, failing clutches present some distinct symptoms.

Slipping
Failing clutches are often said to be "slipping," which is exactly the sensation drivers report. The clutch may feel as though it is not fully disengaging or engaging (if the clutch is failing, this is likely accurate). Slippage will be most noticeable when the engine is dealing with a heavy workload, such as when accelerating to pass another vehicle, traveling uphill or pulling a trailer. As the clutch slips, it overheats and incurs additional wear; this not only accentuates the problem but may cause additional damage to the already failing clutch.

Noise and Jerking
While all clutches eventually and inevitably wear down (via the friction they use to exercise control), noise from the clutch and jerking motions can indicate premature failure. This can be caused by oil contamination from several sources: the seal on the main crankshaft, the transmission input shaft or even engine oil. When oil contaminates the clutch facings, they may grab unevenly, causing jerkiness when the clutch is initially engaged. It may also slip when under a heavy workload.

Foul Smell or Burning Odor
When the clutch temperature gets too hot, either caused by the driver "riding the clutch" or driving aggressively, the facings may become overheated and begin to burn, giving off a peculiar odor. If the clutch has no chance to cool, it may be ruined as may the flywheel and/or pressure plate. Once the clutch disc has been worn beyond a certain point, the clutch may begin to slip noticeably.

Master and Slave Cylinders
Sometimes clutch-related problems can actually be the clutch linkage (or other parts) rather than the clutch itself. Many newer automobiles feature master and slave cylinders with internal pistons with seals that can develop leaks; this may result in the clutch failing to disengage fully or even causing it to engage prematurely. Slave cylinders are more likely to leak since they are situated lower than the master and are more likely to see fluid collect and leak through the seals.

SoarinZHP
09-08-2011, 03:37 PM
Good info!

UncleSmitty
09-08-2011, 05:05 PM
For what it's worth, I think it's clutch slippage. Looks like the engine RPMs are too high on the upshifts, and the clutch is slipping enough to slowly bring the revs down to match the trans speed (instead of gripping hard, jerking the card forward and dropping engine speed quickly).

danewilson77
09-08-2011, 05:08 PM
For what it's worth, I think it's clutch slippage. Looks like the engine RPMs are too high on the upshifts, and the clutch is slipping enough to slowly bring the revs down to match the trans speed (instead of gripping hard, jerking the card forward and dropping engine speed quickly).

Lol.....

HTC Thunderbolt+TT

webster
09-08-2011, 06:17 PM
Lol.....

HTC Thunderbolt+TT

:dueling

lilcdkey
09-08-2011, 06:22 PM
I'm pretty sure its your clutch slipping like everyone else is saying. Happened to my E36.

danewilson77
09-08-2011, 06:23 PM
I'm pretty sure its your clutch slipping like everyone else is saying. Happened to my E36.

:eeps

HTC Thunderbolt+TT

bcleaver
09-08-2011, 06:52 PM
Could someone explain to me how a slipping clutch would result in RPM bog? I get it that other people that have had clutch issues had their car behave in a similar way so I'm not going to dispute that. I just want to understand the physics behind how a free revving engine (which is what we're talking about when the clutch does not engage) would not create lower RPM's, not higher. EVERY bad clutch I've ever seen results in it not egaging properly, meaning that the revs outpace the engagment and the rpm's shoot up because the transfer of power does not engage the tranny. If someone can articulate how what that video is showing is clutch slippage I'd love to be educated.

Johnmadd
09-08-2011, 07:02 PM
The slip is the hi rev and the dip in rpms is when it engages fully, or as much as a worn clutch can. Think of doing a burnout and tires, the tires slip until they grab and as that happens the rpms go high until they grab then the rpms go lower. Make sense?

I thought this was a good explanation.

bcleaver
09-08-2011, 07:22 PM
I thought this was a good explanation.

I never see the 'high' rpms in the video i guess. It's like he shifts and it just bogs. A slipping clutch would be like his burnout analogy, but once it 'caught' it wouldn't 'dip' in RMP, it would accelerate as normal. If it didn't 'catch' the rpm's would keep going.

Since he said it's not accelerating normally, then it doesn't make sense. It would either 'catch' and begin to accelerate normaly once it did, or it would not catch and rev through the roof.

In neither case would it 'bog'.

Johnmadd
09-08-2011, 07:32 PM
Really, that video is not bogging, the ride me and dw took was true bogging when his fuel pump went out, remember Dane? Op's engine sounds normal.

bcleaver
09-08-2011, 07:41 PM
Really, that video is not bogging, the ride me and dw took was true bogging when his fuel pump went out, remember Dane? Op's engine sounds normal.

It's a little hard to tell what's going on in the video, but I was partially going off the title of the thread "RPM's bogging down during hard acceleration" to judge if it was bogging or not according to the OP.

kayger12
09-08-2011, 07:54 PM
Since he said it's not accelerating normally, then it doesn't make sense. It would either 'catch' and begin to accelerate normaly once it did, or it would not catch and rev through the roof.

In neither case would it 'bog'.

Looks to me like the tach is slowly settling to the rpm associated with the next gear while it takes it's time to "catch". Pretty much exactly what UncleSmitty was saying above. :dunno

After careful consideration and umpteen views of the video, I'm on the slipping clutch bandwagon for this one.

Certainly could be wrong. Looking forward to the official diagnosis.

Johnmadd
09-08-2011, 07:56 PM
Looks to me like the tach is slowly settling to the rpm associated with the next gear while it takes it's time to "catch". Pretty much exactly what UncleSmitty was saying above. :dunno

After careful consideration and umpteen views of the video, I'm on the slipping clutch bandwagon for this one.

Certainly could be wrong. Looking forward to the official diagnosis.

Bart Scott.

AzkotikBMW
09-08-2011, 10:25 PM
OP, have you ever replaced your crank sensor?

I have not. Another friend said that MAY be the issue.

But, either way, since my SES light is always on due to the Ebay headers, I can't tell if there are any new codes being thrown (aka ones i didn't know about)

I am going to take it into a shop and get the codes read and go from there.

danewilson77
09-09-2011, 04:20 AM
I think it might be the clutch :shifty

zj96sc
09-09-2011, 05:05 AM
This is why you don't drive around with a SES light.

If I were to throw my 2 cents in, this is not a clutch slipping problem, it is a clutch engagement speed problem. Something is wrong with your clutch MOVEMENT, not the holding force of the clutch once clamped up. Maye failing master or slave, clogged CDV leading to even longer engagement times, problem with the throwout bearing leading to poor movement, etc. Are gears hard to engage when sitting still?

The car accelerates the entire time even as soon as the next gear is engaged so I do not think it is an engine power loss problem. I also think you are exacerbating the problem with poor driving technique. I'd stop doing what you're doing because I'd bet $5 you are absolutely raping your clutch. Do you smell friction material after a pull like this?

What a thread.

Hornung418
09-09-2011, 05:11 AM
Also...OP, you should look into a wideband Oxygen sensor. That will give you more control over the engine and get rid of your SES light. Just a thought.

llll1l1ll
09-09-2011, 07:48 AM
Would gears being hard to engage while sitting still be a sign of a faulty throw out bearing, CDV or even pressure plate?

Marcus-SanDiego
09-09-2011, 08:27 AM
A lot of sniping in this thread. Unnecessary. Let's be better than that.

Question: Kyle, when are you taking this to the shop?

telijah
09-09-2011, 10:04 AM
Would gears being hard to engage while sitting still be a sign of a faulty throw out bearing, CDV or even pressure plate?

It could be, but you would likely have other symptoms too if it were the clutch. Synchros could be going...

AzkotikBMW
09-09-2011, 11:47 AM
A lot of sniping in this thread. Unnecessary. Let's be better than that.

Question: Kyle, when are you taking this to the shop?

Sorry Boss, didn't know it would be such a controversial question =\

I am hoping to get it into the shop next Friday.

And I haven't driven it like this since I took that video, for fear of doing more damage to the car. :(

Marcus-SanDiego
09-09-2011, 11:54 AM
Kyle, no worries. We're all passionate about our cars. We're also passionate about having answers.

Good luck getting to the bottom of things.

AzkotikBMW
09-09-2011, 12:12 PM
Have my appointment set for next Friday with Seth @ JB Eurotech. They do great work and Seth is a really good guy!

Marcus-SanDiego
09-09-2011, 12:32 PM
Good. I'm sure you'll follow up with us.


Sent from my iPhone using Tapatalk

Oli77
09-09-2011, 02:52 PM
The more I look at the video, the more I am thinking there is not much wrong.
You hit 80 mph in ~14 sec and 95 mph in ~18 sec, is that bad?

Also, it is normal for RPM to dip when you switch to a higher gear, that's the whole idea (and the reason you have 6 gears).

Nevertheless, I find this thread interesting and a good learning experience.

I am also curious if the dual mass flywheel might not be involved: See symptoms here (http://forum.e46fanatics.com/showthread.php?p=11086298)

Not sure I understand this video.


http://www.youtube.com/watch?v=YnaXB8q3uzQ&feature=player_detailpage

VA//M3
09-09-2011, 05:09 PM
Have my appointment set for next Friday with Seth @ JB Eurotech. They do great work and Seth is a really good guy!

He should get you sorted out, no prob!

I've had my battles with Seth but he does know what he is talking about and is an all law abiding and environmentally conscious service tech. So he will make sure your car is running in tip top shape as to reduce emissions!

:innocent

VA//M3
09-09-2011, 05:17 PM
The more I look at the video, the more I am thinking there is not much wrong.
You hit 80 mph in ~14 sec and 95 mph in ~18 sec, is that bad?

Also, it is normal for RPM to dip when you switch to a higher gear, that's the whole idea (and the reason you have 6 gears).

Nevertheless, I find this thread interesting and a good learning experience.

I am also curious if the dual mass flywheel might not be involved: See symptoms here (http://forum.e46fanatics.com/showthread.php?p=11086298)

Not sure I understand this video.


http://www.youtube.com/watch?v=YnaXB8q3uzQ&feature=player_detailpage

Our flywheels are designed this way

http://www.zf.com/media/media/img_1/brands_1/sachs/products_sachs/clutches_sachs/planetary_DMF_SACHS.jpg

The spring movement is exaggerated on that video. Even if the springs collapsed inside the blocks (mechanical stops) would keep the flywheel from free spinning and would instantly meet themselves and try to break the tires loose as a result instead of just slipping and then grabbing.

The springs collapse anyway when you dump the clutch and or shifting properly--That is by design.

Oli77
09-10-2011, 10:38 AM
Thanks for the info VA. So not likely that the flywheel is involved in OP's problem (if he does have a problem).

Oli77
09-14-2011, 05:42 PM
Inquisitive minds want to know!

bcleaver
09-19-2011, 06:12 PM
So, what's the word?

Johnmadd
09-19-2011, 08:08 PM
So, what's the word?

+1