[Bulti]

I replaced mine at about 100k miles. I had to replace the oil pan gasket anyway. I checked them using plasti gage. The bearings were well within spec.


The parts themselves aren't expensive so I replaced them anyway. And to my surprise: very little sludge too.


MCL, if your oil pressure is good and you don't track the car, I wouldn't worry too much. Just use the correct oil viscosity and change it as described in the manual.

Partial Post: Please Login or Register to read the full post.

[ds968]

My oil pressure was always at ideal levels ,in every situation ( idle, acceleration, boost, etc.. ) as was the oil temperature ( I have a gauge for that in the tiptronic ) . Just FYI, for whatever it may be worth..


I called the shop today but no news just yet ; due to a number of days of consecutive rain ( which immediately throws the entire SoCal region into apocalyptic panic and everything comes to a grinding halt ) the shop had to delay some things to move cars around and get this one inside, so it was only yesterday that the engine was pulled out and is now on the bench ready to be opened up ..tomorrow or Thusday we should have the initial findings.

Partial Post: Please Login or Register to read the full post.

[Bulti]

I would be surprised if the rod bearings caused all this. I hope that at least the transmission is still fine. Fingers crossed Dan.

Partial Post: Please Login or Register to read the full post.

[ds968]

That piece ( pictured in the earlier post ) found at the bottom of the oil pan is almost certainly a piston ring . I think the rod bearings theory came into play because of the engine seizure where the crank could not be turned manually even one mm in any direction. But if a piston is frozen inside the cylinder I would imagine that would be the result as well. Oh well, all speculation until a couple of days from now when everything is taken apart. Yeah, I hope the transmission is ok, flash suggested the fluids and the filter be changed just because we're not entirely sure if that was done when the new flex plate was installed ( about three years ago ) , logic would tell you the shop must have done that as part of the job, but who knows ..? Also hoping the engine oil that was sucked through the intake and went into the SC did not cause any harm, because it might have had some impurities ( metallic flakes ?! ) contamination, but it looked free of any such things so fingers crossed there as well.

Partial Post: Please Login or Register to read the full post.

[ds968]

Still no news, but an interesting development related to the momentarily stuck RPMs symptom in the 968. Driving my MBZ today also around 60 mph and also in D ( it's a similar " tiptronic " transmission ) I stomped on it to see just how fast it shifts and/or drops the RPMs when it gets to the redline, although this car's redline is at 6 k. Interestingly enough it also hangs right about the redline level for that same one or two seconds and then it shifts ,and drops the RPMs but at an even slower rate than the 968. So now I wonder if this is a deliberately programmed m.o. for tiptronics in German cars ? If that was the case, it could certainly be a relief that my car's brief rpm hanging was not really unusual but that one or two seconds sure seems like an eternity ..

Partial Post: Please Login or Register to read the full post.

[wildcat]

6700?

I never glanced at my tach that closely, I thought it was at 6500.  But just to confirm that it does indeed go to redline (6700?) I took it for a spin and in first gear in manual drove it right up to redline where it shifted on its own.  I have also on a couple of occasions driven it into the red by doing what you're not supposed to be able to do, which is push the auto mode from D to N. I did this thinking I was in manual mode. Really startled me, but the engine is tough. I blew up a 427 running it in red just before a shift, bent a push rod. 

Partial Post: Please Login or Register to read the full post.

[wildcat]

Still no news, but an interesting development related to the momentarily stuck RPMs symptom in the 968. Driving my MBZ today also around 60 mph and also in D ( it's a similar " tiptronic " transmission ) I stomped on it to see just how fast it shifts and/or drops the RPMs when it gets to the redline, although this car's redline is at 6 k. Interestingly enough it also hangs right about the redline level for that same one or two seconds and then it shifts ,and drops the RPMs but at an even slower rate than the 968. So now I wonder if this is a deliberately programmed m.o. for tiptronics in German cars ? If that was the case, it could certainly be a relief that my car's brief rpm hanging was not really unusual but that one or two seconds sure seems like an eternity ..

As I mentioned in the last post, I just drove mine right up to redline and it shifted immediately, no hesitation. That was in first gear, I'll try it between 2 and 3 to see if there's any difference... maybe this weekend, too much weekday traffic around here to take my eyes of the road to watch it shift. 

Partial Post: Please Login or Register to read the full post.

[ds968]

Yes, mine also always shifted immediately from 1st to 2nd to 3rd to 4th as soon as it hit the redline..tne brief hesitation happened in only one situation and that was when it dropped from 4th to 2nd on wot and the ensuing rpm was immediately pushed to the redline

Partial Post: Please Login or Register to read the full post.

[flash]

there is something wrong if you can run past redline.  the fuel cutout is non-negotiable.  as for the tip running to redline, it isn't supposed to in tip mode, and should shift at a bit over 5k, and even in manual mode, it should shift before redline.

Partial Post: Please Login or Register to read the full post.

[ds968]

I'll pay closer attention today to the tach, I thought it was right below the redline ( both the 968 and the MBZ ) but maybe it just seemed that way from the blink of an eye glance at the tach at the time . But extremely doubtful it was only at 5 k , and I know for a fact that the 968 tip normally shifts only when well over 5k, perhaps 6k but not less.

Partial Post: Please Login or Register to read the full post.

[flash]

i said a bit over.  i can't remember exactly where, but it was well under 6k

 

in manual mode, once you hit program 5, i suppose it could go higher, but i know for a fact that i could not get it to redline in 3rd, even in manual mode, which is where i needed to be in order to dyno the car.  no matter what i did, no go.  keep in mind that i had likely the best possible chance too, as this was on a car with only 25k on it, and a recently serviced trans that showed absolutely no signs of anything out of the ordinary.

 

the only way to know for sure that you hit redline is to hit the fuel cutout point.  this is set by the computer.  these tachs are not known for being bang on, so it's easy to think you are at redline, and be 500 off of that according to the tach.  in fact, many car manufacturers actually set the tachs to be off, and read high, so that you don't actually get there and blow something up.

Partial Post: Please Login or Register to read the full post.

[ds968]

I never hit the fuel cutoff point in the Tip. Did that a few times however in the six speed, before the SC days, so when it was NA, but dont t recall if it was Lao before or after the X-Racer chip mod.

Partial Post: Please Login or Register to read the full post.

[wildcat]

I've never hit the fuel cutoff point either.  As for the down shifting from 4 to 2, that's a hard jam, and it is immediate, not the kind of thing you'd miss unless of course as in your case there's a delay. As for the tach, VDO is known to be a little flakey but mine would not appear to be off by 500 rpm.  The dial is incremented by 5.  The third mark; redline, is at 6600 and that is within a hairs width where it shifts so I'm confident the tach is accurate. As for tip mode I experienced some lag about a year ago, and that strange phenomenon where the tip doesn't shift down as its supposed but is delayed. I've bled the transmission fluid a couple of times since then but have concluded that the 968 needs to be driven regularly and robustly to operate at its potential. The only other factor I've changed is the generator which has been replaced and is putting out a solid 13.5 volts. A mechanic mentioned that the belt needs to be fairly tight and slippage can reduce its output when you think its operating properly because the gauge is on the low side between 12 and 13. It should remain stable. Mine would start out high (around 13.5) and then drop to around 12.5 out on the highway. Now it will drop to around 13 at its low. I mention this because there's a lot of wiring between the  DME and the Tip. These computers need a stable supply. That small battery acting as a capacitor is not enough to buffer the output of a weak generator. I doubt this is your issue but I mention it anyway. 

Partial Post: Please Login or Register to read the full post.

[wildcat]

O.K. so the range of 2nd gear is broad and the tip will go into fourth when cruising.  At 60mph (the speed that was mentioned) the rpms are too high to drop into 2nd, so instead I cruised it at 40mph and got on it, it drops to second like a passing gear in a typical automatic.  FWIW

Partial Post: Please Login or Register to read the full post.

[ds968]

The rpms are too high at 60mph in D to drop to 2nd ?  Not sure about that because it would then mean it drops only one gear to 3rd and there is no way the rpm would immediately go to the redline in 3rd..  IMO...   

Partial Post: Please Login or Register to read the full post.

[wildcat]

That may be were the 5500 limiter kicks in because it does not kick in before redline when powering up. I'll do some more checks. 

Partial Post: Please Login or Register to read the full post.

[wildcat]

"The Porsche Tiptronic is a four speed transmission which may be shifted while under load. This permits extremely short gear shifting time without interruption of power flow."

At 60 a rapid compression of the accelerator will shift it down from 4 to 2 as you've stated, while a more moderate compression of the accelerator will drop it from 4 to 3 which is what I'm accustom. It seems easier to go from 4 to 2 at 40 than at 60, the force exerted doesn't seem proportional. Either way the response is immediate.

Partial Post: Please Login or Register to read the full post.

[ds968]

And now here are the photos of the carnage, prefaced by the mechanic's brief  note :   
" I took the motor apart and looks like the engine detonated possibly from running too lean at high RPMs.  The # 4 piston is damaged with the cylinder wall.  The head is also damaged, but repairable.  The metal shavings got to the bearings as well and scraped the crank.  The oil passages of the crank are filled with metal shavings, but it can be saved. " 



BTW, he does have a spare engine, but he has to take it apart to make sure the block is in top shape , smooth cylinders, pistons , etc..

               

 

Looking at that cylinder wall, I'm thinking a dab of rubbing compound on a microfiber cloth should be able to restore it back to normal     

   

Partial Post: Please Login or Register to read the full post.

[ds968]

this photo refused to load along with the rest..even after I had it re-sized to as small as the program would allow

 

   

Partial Post: Please Login or Register to read the full post.

[flash]

that'll buff out - no problem

Partial Post: Please Login or Register to read the full post.