Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)
saraf

Broken oil pump shaft/ motor over rev

Recommended Posts

SPIRO, I think that whoever was using it was abusing it, that's why Porsche denied the replacement. I've made these comments to others, that you can't expect any manufacturer to repair or replace components if they have been abused by you or anyone else. People may say they will, but I believe they will be in for an uphill battle in court.

And if the dealer did in fact track/abuse this car, you should contact the dealer and inform them of your plight, and get them to take responsibility and pay for it.

Anyways just my 2c.

Cheers :)

Thanks for the input.

There is only one dealer in our town.

They take the attitude that "who are you and why are you complaining to us". Porsche North America was not much help either.

I love the car but the personnel at the dealership have no concept of client service and relations. I wondered why some of the new Porsche owners were travelling to the West Coast area, Vancouver to purchase their cars.

Anyway

Thanks

Share this post


Link to post
Share on other sites
    You can remove these ads by becoming a Contributing Member.

You know, this thread got me thinking, and there are, strange as it may sound to others, instances where a "demo" or "sales mgr" car has been used at the track. I've seen it, and these vehicles have been flogged to the limit, so the accrued damage may have been in some way contributory. This type of scenario would indicate then that it is not the best idea to buy demos or manager's cars, and that a DME download and a comp test are critical components within the buying process.

Thanks for your thread Saraf, I'm sure many others have learned a lot from your unfortunate situation.

Cheers all :)

Share this post


Link to post
Share on other sites

White, on the sheet they gave me it was a 2 page summary with this plus a bunch of other data, possibly similar to what Saraf has. I'm not positive about specific timing because I did not ask, but got the impression that they "could" determine when each hit occurred. This is just speculation though, as even the dealer may not be privy to all the data contained within the black box.

That's the best answer I can give you. It was the 6 ranges I noted herein (and confirmed by Saraf), and the # of ignitions in each range. The dealer did inform me to keep the # of ignitions down as much as possible to avoid engine damage. Rev limiter acceleration is not recommended, even though that's what a rev limiter is for (ie engine protection).

Cheers :)

Share this post


Link to post
Share on other sites

Unforunately this info must be wrong. You cant have 1 ignition in range 3 then more in 4 & 5.

Share this post


Link to post
Share on other sites

Bosch and Siemens have the possibilities to extract 80% more info from the DME than the dealer, that's way the DME become withdraw in case of doubts.

Share this post


Link to post
Share on other sites

I agree John, that makes no sense given the # of hits in the higher ranges. That single lower hit would seem very unlikely. But if his data is correct, the DME only spits out what it has. You're quite observant though, I noticed that also when I first saw that. It is plausible, but unlikely imo. He may have just typed it incorrectly. I, like many have the odd typo here and there, even though I try proofreading a couple of times to check.

Anyways cheers :)

Saraf did say he was just going to pay anyways - it seems like a done deal to me, this is just blah, blah, blah.

Edited by eqs

Share this post


Link to post
Share on other sites
I agree John, that makes no sense given the # of hits in the higher ranges. That single lower hit would seem very unlikely. But if his data is correct, the DME only spits out what it has. You're quite observant though, I noticed that also when I first saw that. It is plausible, but unlikely imo. He may have just typed it incorrectly. I, like many have the odd typo here and there, even though I try proofreading a couple of times to check.

Anyways cheers :)

Saraf did say he was just going to pay anyways - it seems like a done deal to me, this is just blah, blah, blah.

I may pay upfront to get my Porsche back but they either pay or this continues to claims court.

Thanks for the information.

More questions

Information from a mechanics says that when the car is down shifted from say 3rd to 2nd and the clutch is released the wheels will drive the motor revs as shown on the tachometer in a straight line to the highest rev attainable from the energy coming from the back wheels. The increase of revs should be constant and equal till it reaches the top end. Ok. If the motor is over reved the computor will start recording the ignition hits (6 per rpm- 6 cylinder motor) through the ranges. Range 1 being 7300- 7500, range 2 being 7500 to 7700 and so on. Since the motor increases in a straight line the ignition hits should be basically the same in all the ranges until it tops off, with perhaps 1 or 2 hits at the very top end. The computor read out that the Porsche service manager gave me had 4244 ignition hits in range 1, 466 in range 2, 5 in range 3, 1 in range 4, 256 in range 5, 1 in range 6. . If the car was down shifted and the wheels drove the motor why did the revs go to 7400 (average between 7300 and 7500) and stay there for approximately 6 seconds and then take off to 9500 rpm. This data is not consistant with data from other down shift computor logs. Remember the driver has no effect on the revs with the gas pedal after 7000 rpm is reached. The over revs if not caused by the assumed downshift had to be caused by something in the motor computor system. Since the basis of denying a warranty claim is the assumed down shift, the denial will not stand up. Any thoughts.

Thanks

Share this post


Link to post
Share on other sites
I agree John, that makes no sense given the # of hits in the higher ranges. That single lower hit would seem very unlikely. But if his data is correct, the DME only spits out what it has. You're quite observant though, I noticed that also when I first saw that. It is plausible, but unlikely imo. He may have just typed it incorrectly. I, like many have the odd typo here and there, even though I try proofreading a couple of times to check.

Anyways cheers :)

Saraf did say he was just going to pay anyways - it seems like a done deal to me, this is just blah, blah, blah.

Thanks for the input see my reply on other post. What the computor says is not consistant with what the Porsche service manager is trying to sell me.

Thanks.

Share this post


Link to post
Share on other sites
Unforunately this info must be wrong. You cant have 1 ignition in range 3 then more in 4 & 5.

Hi

Thanks for the discussion.

Your thought is the same as mine. It did not make sense if the assumed downshift was to blame for the over rev, but if the computor or motor malfunctioned because of internal parts failure, then it starts making sense.

Their basis for warranty denial is driver downshift. this data will prove that the data from their own machines does not prove their assumption.

Thanks

Share this post


Link to post
Share on other sites

An update to this issue. I had the motor replaced by a qualified, competent and professional garage and the Porsche runs sweet.

They dumped the information from the computer and they found the information that it contained.

Contrary to the statement that the Porsche dealership made that it could not find the time date stamp when the motor over revved and it must have been the moment before the motor broke; this new information dump said something totally different.

The car has 891.4 operating hours on it when the motor damage occured. The revs at range 1, 7300-7500 rpm and range 2, 7500-7700 rpm, happened before and up to operating hour 828. The four ignition hits in range 3 to 6 happened up to or on operating hour 164, 727 operating hours before the motor broke. The mechanic will attest that 4 ignition hits is not enough to make a motor break.

I have a feeling that the Porsche dealership had the time date information but would not share this with me so they get me to pay for the motor and then claim warranty costs from Porsche.

I am a happy camper since this is hard evidence that Porsche will have to address.

Happy, top down motoring in the city today.

Share this post


Link to post
Share on other sites
An update to this issue. I had the motor replaced by a qualified, competent and professional garage and the Porsche runs sweet.

They dumped the information from the computer and they found the information that it contained.

Contrary to the statement that the Porsche dealership made that it could not find the time date stamp when the motor over revved and it must have been the moment before the motor broke; this new information dump said something totally different.

The car has 891.4 operating hours on it when the motor damage occured. The revs at range 1, 7300-7500 rpm and range 2, 7500-7700 rpm, happened before and up to operating hour 828. The four ignition hits in range 3 to 6 happened up to or on operating hour 164, 727 operating hours before the motor broke. The mechanic will attest that 4 ignition hits is not enough to make a motor break.

I have a feeling that the Porsche dealership had the time date information but would not share this with me so they get me to pay for the motor and then claim warranty costs from Porsche.

I am a happy camper since this is hard evidence that Porsche will have to address.

Happy, top down motoring in the city today.

I'm curious to know how this turns out...kindly update as the situation develops. good luck...

Share this post


Link to post
Share on other sites
An update to this issue. I had the motor replaced by a qualified, competent and professional garage and the Porsche runs sweet.

They dumped the information from the computer and they found the information that it contained.

Contrary to the statement that the Porsche dealership made that it could not find the time date stamp when the motor over revved and it must have been the moment before the motor broke; this new information dump said something totally different.

The car has 891.4 operating hours on it when the motor damage occured. The revs at range 1, 7300-7500 rpm and range 2, 7500-7700 rpm, happened before and up to operating hour 828. The four ignition hits in range 3 to 6 happened up to or on operating hour 164, 727 operating hours before the motor broke. The mechanic will attest that 4 ignition hits is not enough to make a motor break.

I have a feeling that the Porsche dealership had the time date information but would not share this with me so they get me to pay for the motor and then claim warranty costs from Porsche.

I am a happy camper since this is hard evidence that Porsche will have to address.

Happy, top down motoring in the city today.

I'm curious to know how this turns out...kindly update as the situation develops. good luck...

Just an update.

Happily I have my ride back on the highway and running perfect.

I have collected the hard data on paper with the requisites written statements backing up the data from qualified personnel and am proceeding in discussion with a lawyer to move forward in small claims court.

Dealership responded to the Better Business Bureau investigation by saying that I got angry for no reason and removed the car before the had a chance to fully investigate the situation.

Justice moves slowly but I am confident the "black box" data proves them incorrect.

Take care

Relaxed motoring

Share this post


Link to post
Share on other sites

I did the math on this and I got some strange results. Is this because the rev ranges for my 986S are not the same as those listed, or are there multiple ignitions (like an MSD box) during a single power stroke? Can someone verify please...

Foremost assumption: Given a Porsche motor that is 4 stroke and 6 cylinders, I get 3 ignitions per rev.

Now I am religious about shifting BEFORE 7200 rpm (usually 6800 rpm), yet my DME tells me that I recently had 5672 ignitions in Range 1! Crunching the numbers equates to roughly 15 sec. of over revving!!! That's impossible from my experience. If anything I might have bumped it maybe for a second or two. Also, I am the sole driver of the car. What gives? Either my math is wrong, my tach is funky, there's MSD type ignitons, the DME is fudging, or the ranges are lower for my 986S.

I've ran into the limiter before, and I could feel the power get pulled out. Though I've never tried, I would imagine this would safeguard against "normal" over-revs into ranges 2-6, assuming no mis-shifts and just plain old acceleration from the accelerator pedal.

Something doesn't add up. I do hope you get a favorable judgement saraf... at least you are enjoying the car again. :D

Edited by demonz

Share this post


Link to post
Share on other sites

I just realized the ignitions are probably cumulative. That would make sense then, for my case anyways...

Share this post


Link to post
Share on other sites

Saraf, any follow up for us? Did Porsche come through with some payment for your repairs?

Share this post


Link to post
Share on other sites
Saraf, any follow up for us? Did Porsche come through with some payment for your repairs?

Sorry, summertime and the top is down and am cruising in the sunshine.

A qualified garage in the city that does work on Porsche, BMW, Ferrari and Lamborghini dropped a new Porsche motor in. They pulled the DME information and will swear that the motor did not break because of any over rev.

So we are off to small claims court or an arbitration panel that if binding.

Thanks for the continued interest in this event.

I will keep you informed as best I can.

Saraf

Share this post


Link to post
Share on other sites

Man! I wish you the best on this. It's good you got the car back on the road so your not waiting for it to get fixed. I agree with the mechanic that only a few over-rev's won't destroy the motor (unless its ridiculous). The modified redline on my 944 is 7000, I had a bad downshift when racing and maybe hit 8500+. It's still ticking.

I just hope this isn't going to be a common problem with 987 motors.

Share this post


Link to post
Share on other sites

I was at the track last month and shifted from 2nd to first by mistake. It made a noise after that and the dealer replaced my transmission and flywheel under warranty. They said the ring gear and pinion were damaged. I don't think I left the clutch out enough to overrev the engine. I'm suprised there aren't any rev limiters on a downshift.

Share this post


Link to post
Share on other sites
I was at the track last month and shifted from 2nd to first by mistake. It made a noise after that and the dealer replaced my transmission and flywheel under warranty. They said the ring gear and pinion were damaged. I don't think I left the clutch out enough to overrev the engine. I'm suprised there aren't any rev limiters on a downshift.

How would one be able to stop a over rev from a downshift??

Share this post


Link to post
Share on other sites
I was at the track last month and shifted from 2nd to first by mistake. It made a noise after that and the dealer replaced my transmission and flywheel under warranty. They said the ring gear and pinion were damaged. I don't think I left the clutch out enough to overrev the engine. I'm suprised there aren't any rev limiters on a downshift.

How would one be able to stop a over rev from a downshift??

Good point

Share this post


Link to post
Share on other sites

Under acceleration the rev limiter cuts fuel to 3 of the 6 cylinders. That is why it fells like the car is running out of gas when you hit the rev limiter. That is how the engine is protected from high rpms.

But when you miss a downshift the rev limiter cannot protect the engine, as the high engine rpms are created by the wheels and the car moving forward. Not a mechanical engineer, but you would need some type of mechanical device to disconnect the transmission rpms from the engine when a certain rpm was reached. Like a clutch for the flywheel. Such as device would have to be able to function in a split second.

Share this post


Link to post
Share on other sites

So the question about how an engine could be protected from overrev on downshift comes up occasionally. It got me to thinking how it might be done.

With an automatic or manumatic its not an issue. The computer calculates what the RPM would be if it allowed the downshift. If the RPM are above redline then the downshift is not allowed.

But with a manual there is no computer control. Any shift that the driver physically makes is acted upon AS SOON AS THE CLUTCH PEDAL IS RELEASED. So why not have the computer not allow that release if it calculates resulting RPM would be too high? The clutch is hydraulic. Some simple computer controlled valving could probably be engineered to override the clutch release by the driver.

Do I think that any manufacturer will ever do this? No. The direction is towards PDK type trannies. There is no upside for the manufacturer to make an overrev-proof manual transmission motor. But it still is an interesting thought.

Regards,

Alan

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.