Engine trouble - "Tach Jump" causing power loss - ANY IDEAS?

[ronnyek]

You should see my problems with my g35... > 3qts burned in 3kmi, and when you let off the gas under heavy acceleration (eg to shift) a LOUD RAAAAAAAAAT sound (like old 1inch glasspacks on a mexicans lowrider)

Infiniti dealer says all is normal... could explain it over and over and over and prove my friends identical g35 doesnt have that problem and they refuse to do anything for me.

[Night1]

Update:

The Service Manager at the BMW dealership actually took my Riss Racing intake off and put a stock intake on to test my car, and found out that my problem is not being caused by the Riss Racing intake. That was very nice of them to do that and it saved me the hassle of having to pick up my car, swap intakes, etc. :w00t:

They received authorization this morning to update the software in my car. They said that the new update offers performance enhancements and might solve the problem. If not, they will continue to explore further.

I mentioned all the possibilities to the Service Manager, including oil in the clutch, bad clutch, boost leak in the intake system, etc. He says he will explore these possibilities and get into the mechanical repairs if the software update is unsuccessful.

In the meantime, I've been without my baby for a week, and this 328i loaner is sooooooooo weak on power. I miss my car! :wub:

[jeremyc74]

Originally Posted by Night1

Update:

The Service Manager at the BMW dealership actually took my Riss Racing intake off and put a stock intake on to test my car, and found out that my problem is not being caused by the Riss Racing intake. That was very nice of them to do that and it saved me the hassle of having to pick up my car, swap intakes, etc. :w00t:

They received authorization this morning to update the software in my car. They said that the new update offers performance enhancements and might solve the problem. If not, they will continue to explore further.

I mentioned all the possibilities to the Service Manager, including oil in the clutch, bad clutch, boost leak in the intake system, etc. He says he will explore these possibilities and get into the mechanical repairs if the software update is unsuccessful.

In the meantime, I've been without my baby for a week, and this 328i loaner is sooooooooo weak on power. I miss my car! :wub:

The fact that they actually though an intake could have ANYTHING to do with this, or that a software update is going to fix it is just absurd. There is no possible way software could cause a disconnect between engine RPM and vehicle speed on a car with a manual transmission. They're trying to avoid the real problem, which is an issue with the clutch.

[Lester]

Originally Posted by jeremyc74

The fact that they actually thought an intake could have ANYTHING to do with this, or that a software update is going to fix it is just absurd. There is no possible way software could cause a disconnect between engine RPM and vehicle speed on a car with a manual transmission. They're trying to avoid the real problem, which is an issue with the clutch.

I agree - but they have to follow BMW Protocol, or they won't get paid for the repair.

[Night1]

Originally Posted by Lester

I agree - but they have to follow BMW Protocol, or they won't get paid for the repair.

Yeah, I agree that's what's going on here.

[ChrisK]

Originally Posted by Night1

Update:

The Service Manager at the BMW dealership actually took my Riss Racing intake off and put a stock intake on to test my car, and found out that my problem is not being caused by the Riss Racing intake. That was very nice of them to do that and it saved me the hassle of having to pick up my car, swap intakes, etc. :w00t:

They received authorization this morning to update the software in my car. They said that the new update offers performance enhancements and might solve the problem. If not, they will continue to explore further.

I mentioned all the possibilities to the Service Manager, including oil in the clutch, bad clutch, boost leak in the intake system, etc. He says he will explore these possibilities and get into the mechanical repairs if the software update is unsuccessful.

In the meantime, I've been without my baby for a week, and this 328i loaner is sooooooooo weak on power. I miss my car! :wub:

I wonder what version of software you will get?

[SV Concepts II]

Originally Posted by 123D-M

This sounds exactly like the problem I have been having. Clutch slips immediately after an up-change. Car hesitates or sometimes jerks a bit while the clutch is struggling to grip, then it goes as normal.

FYI. I've already had my clutch and gearbox replaced as when BMW opened it up they discovered that oil was leaking into the clutch. This was causing the slip when you change gear and it eventually caused my clutch to be completely fried. Unfortunately for me, even after having everything replaced it has started doing it again so it is going back to the dealer after xmas.

Anyway, the point is, that slip after a gearchange is almost certainly caused by oil in the clutch. PM me if you want further details. I'm 99% sure that the clutch mechanism would be the same between a 123d and a 135i.

I was thinking the same thing. It could be the input shaft seal has sprung a leak and is soaking the clutch.

[jeremyc74]

Originally Posted by Lester

I agree - but they have to follow BMW Protocol, or they won't get paid for the repair.

I'm sure that's the case. I just can't believe BMW would want them to waste the additional time on something that's obviously not the problem.

[Lester]

They start with things that might work, but are relatively inexpensive. Then they move up the ladder from there. The idea is to save themseves money.

[imdanomite]

^^ ding ding ding! that's right. why pay the tech hours on hours to pull a tranny off? start with the easy, low paying jobs first.

you'd be surprised at what an aftermarket intake can do. luckily, the N54 engine doesn't really utilize the HFM except to measure intake temp.

i haven't seen any clutch issues with the N54 w/ manual trans. these days, programming will fix majority of the problems...believe it or not.

keep up posted on the outcome!!

[jeremyc74]

Originally Posted by imdanomite

^^ ding ding ding! that's right. why pay the tech hours on hours to pull a tranny off? start with the easy, low paying jobs first.

you'd be surprised at what an aftermarket intake can do. luckily, the N54 engine doesn't really utilize the HFM except to measure intake temp.

i haven't seen any clutch issues with the N54 w/ manual trans. these days, programming will fix majority of the problems...believe it or not.

keep up posted on the outcome!!

There's no chance at all of fixing this issue with programming. It's a complete waste of the tech and customer's time, and makes them look like they're dodging the issue to anyone who knows anything about it.

There is no possible way software can cause a disconnect between the engine and driveline on a car with a manual transmission. Period.

[jeremyc74]

Originally Posted by Lester

They start with things that might work, but are relatively inexpensive. .

There's no chance at all of this fixing the problem.

[Night1]

Originally Posted by jeremyc74

There's no chance at all of this fixing the problem.

I will defiintely keep everyone posted if I ever get my freakin' car back!:bangdesk:

[123D-M]

Originally Posted by Ali@Jlevi SW

I was thinking the same thing. It could be the input shaft seal has sprung a leak and is soaking the clutch.

Do you mean the input shaft in the gearbox? I believe that is what they told me was the problem on my car. So they replaced my gearbox.

But now I have the same problem again So it will be going back to the dealer.

[SV Concepts II]

Originally Posted by Night1

I will defiintely keep everyone posted if I ever get my freakin' car back!:bangdesk:

Good luck man.

Originally Posted by 123D-M

Do you mean the input shaft in the gearbox? I believe that is what they told me was the problem on my car. So they replaced my gearbox.

But now I have the same problem again So it will be going back to the dealer.

Yup. I had the same issue on my old E36. The gearbox sprung a leak after I bottomed out hard one day on a speed bump. Turned out the input shaft seal in the gearbox was leaking fluid all over the place (including the clutch).

Hopefully your local techs can pinpoint and resolve both of you guys' issues.

[Night1]

Originally Posted by Ali@Jlevi SW

Good luck man.

Thanks!

Yup. I had the same issue on my old E36. The gearbox sprung a leak after I bottomed out hard one day on a speed bump. Turned out the input shaft seal in the gearbox was leaking fluid all over the place (including the clutch).

Hopefully your local techs can pinpoint and resolve both of you guys' issues.

You know, I didn't even consider that my earlier incident could be connected to this issue. See here: http://www.1addicts.com/forums/showthread.php?t=13859

My car did take a good shock hit w that bump but the only damage I noticed underneath the car was one of the 2 bolts that holds the muffler on came off and had to be replaced.

I'll mention that previous incident to the head tech and have him check that out too.

[Night1]

Update:

They installed the software update on my car and said that it improved the issue but did not totally eliminate it. No surprise there, right?

They are now dealing directly with a BMW field service engineer who has set up a "PUMA Case." As it was explained to me, they have downloaded data from my car and sent it to the BMW service engineers and are awaiting a response from them.

Of course the holidays are causing a delay in their response, so who knows when I'll see my car again.

Has anyone heard of the PUMA thing before? :iono:

[123D-M]

PUMA is the BMW service database. All warranty issues are logged in there so that techs can find out if problems have occurred before. Hopefully BMW should find other similar cases such as mine to tell them what needs doing.

And I'm not surprised that a software update was unable to fix a slipping clutch.

[Night1]

Originally Posted by 123D-M

PUMA is the BMW service database. All warranty issues are logged in there so that techs can find out if problems have occurred before. Hopefully BMW should find other similar cases such as mine to tell them what needs doing.

And I'm not surprised that a software update was unable to fix a slipping clutch.

I hear ya, thanks. Hopefully they will find what they need.

[Night1]

Update: BMW is currently doing a smoke test on my car to check for possible leaks in the vacuum tubes. They admitted today that they have no idea what is wrong with my car. Even 2 BMW field engineers have been sent to inspect it in person, and they are clueless.

If this sh*t continues much longer, I will be looking for a new car.

[Riss Racing]

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[Riss Racing]

Originally Posted by Night1

Update: BMW is currently doing a smoke test on my car to check for possible leaks in the vacuum tubes. They admitted today that they have no idea what is wrong with my car. Even 2 BMW field engineers have been sent to inspect it in person, and they are clueless.

If this sh*t continues much longer, I will be looking for a new car.

They will figure it out I'm sure. Do you have the service records of what they have checked. If so give me a call tomorrow I'll see if I can have our techs help nail down the problem...