Update on Tiptronic Transmission woes...now I really need advice

[ScottArizona]

Well,

My post below chronicled the problems I have been having with my tip...nothing earth shattering, just a car that does not shift right in certain conditions (such as stop and go traffic). The dealer has now had it for a few days, and here is the rub: They say they have tracked down everything it could be, and are still not sure, but that everything is "pointing" to a bad tiptronic control unit. The problem is that the service advisor has quite candidlly told me that once they install the new unit, its mine and that they can't take it back because of something about how it is programmed for a specific car. This would not ordinarily be a problem except that they want 2700.00 for the stupid thing. I have not yet spoken to the tech who is currently out to lunch, but I plan to do so. Here are my questions for the board:

1. Is it in fact the case that once the tcu is installed and programmed it can't be used in another car? I'm trying to figure out if they are just blowing smoke regarding their reason why they would not be able to refund my money if a new tcu does not fix my problem.

2. I have already checked with board sponsor sunset, and they can beat my dealer's price by almost 1,300!!!! I mentioned this to my dealer and they said they would install the party regardless of where I buy it. However, is installing this something that an independent could do, or does the installer have to have the proprietary Porsche software/computers?

3. The service advisor said that a used unit (from a damaged car for example) would not work because once programmed for a car, it can't be reprogrammed. Does this sound right?

4. What do you guys think about the diagnosis? I really don't want to spend 2-3k if this is not going to fix my problem.

Of course, all of this is great timing. Any advice would be much appreciated. Scott.

[Richard Hamilton]

After fitting a new Tiptronic Control Module it is coded for the country, but there are only a couple of options according to the manual. Also the Adaption Values should be reset. That's it - but you need a PST2. I can't see any reason why you couldn't move one from car to car, so I would try and find one at a salvage yard if I were you. And find yourself an independent with a PST2.

[Izzy]

Scott, I am surprise they can not tell you if the control module is it or not. If you like, send me a pm with an email address that I can forward some goodies. There are test point by test point diagnosis (about 40 pages worth) that a dealer with the correct equipment (PST2) should do to rule in or out the module or another component. I used it to get to fix my Tip problem, the dealer tech did not followed the process at all from my perspective. I ended up bringing the printed pages to my dealer, and told them what to do.

And yes, you can get an used module, I have seent them in Ebay, or LAdismantlers too.

[wvicary]

I've not tried this on a Tiptronic but VW uses a very similar transaxle(valve body/ECU mapping) and when we have shifting problems the first thing to do is reset the adaption settings in the ECU. I've seen this procedure cure many simple problems that have been caused by anything from low fluid level that caused cavitation to low battery voltage/battery replacement issues. This also has to be done in relation with the throttle body/kick down switch adaption. I hope this is of some help.

[ScottArizona]

Here is an update. I took the care to a very well respected independent (former factory premier tech with pst2 tester), and he too suspected low fluid. He found the tranny was just under a quart low. he topped it off and sent me on my way to see if the problem was gone. Well, the topping off seemed to help at first but quickly the problems came back. In fact, the poor shifting seems to have gotten worse, and now I am noticing a pronounced rpm surge at low speeds and low rpm in fifth gear upon very slight acceleration.

So, I took the car back, and we opened up the DME that he had ordered just in case. The first thing he noticed were scuff marks and some indented metal where the DME mounts to the car, leading him to believe the DME we recieved was not new and had been mounted before. So, we just popped it in, and wouldn't you know it...no difference. We drove around together for a while and the tech agreed that something was definately not right. He now thinks there are two possibilities: (1) the DME they sent was a core exchange and we should try a new DME; or (2) the other independent shop I had used to do my tranny service in September might have used the wrong fluid. So, we are going to do a new service with fluid change to see if that helps things. Keep you fingers crossed for me, and I'll be sure to give an update once this is resolved. THanks for all your help, Scott.

[Izzy]

I know you have to be tired of spending time and money on this thing, but.... Here some unsolicited information, see if the tech can flush all the fluid out, all 9 liters and refill with the correct fluid. If he (or she, to be PC) can not flush it, then do the change at least 2-3 times. Drain, refill, drive for a while, repeat. The old fluid will mix with the new one and you will not get the old one out by only doing one drain.

The original ESSO is hard to find, dealer only. But Pennzoil makes an equivalent. I think I have the info in the DIY. Good luck, happy new year.

Izzy

[ScottArizona]

Thanks Izzy, that is good advice, and I'll run it by the tech (he has the car right now). The funny thing about all this is that I'm not even that concerned about the cost right now (provided I don't need to shell out for a new transmission or anything). I just want my car back to normal! I'll let you know what happens!.

[Izzy]

You know what you really need? You need a 99 Cabrio 996, Metallic blue with a blue top and tan interior, tiptronic of course, cd changer, etc, etc, etc. Oh, wait a minute, I just happen to have one in my garage for sale, your lucky day! What do you know!!!

Have a great New Year, hope this is done for you so you can go on a nice long ride.

Izzy

Edited December 31, 2006 by izzyandsue

[ScottArizona]

O.k. here is an update, and it's not that good. New DME was installed...no change. All ATF was flushed with a couple of separate drains, replaced with new fluid and filter...still no help. Tech verified the shift mechanism in the center console was in the correct position (it is). Still no codes or faults of any kind. He is basically stumped, as are a few info sources he has consulted. We are not sure where to go from here. The rpm surge is still present at low speed and low rpm in 4th and 5th upon very slight acceleration. Also present is the clunky and shuddering shifting, which seems to be getting worse. I'm not sure what I'm going to do as at this point as future diagnosis attempts will amount to little more than guesses (that will of course be expensive). The next step according to the tech is to verify all the dme wiring is working properly, that nothing has been chewed through or is not grounding somewhere, etc...but that is 3-4 hours labor with no real indication other than a hunch as to whether this is the problem.

Izzy, you've been great, but I assume you are out of ideas. Loren, what do you think? Thanks again for your help guys! Scott.

[Loren]

All of the Tip test procedures are in the OBD II manual for MY99.

I would certainly walk through the tests and the actual readings and then compare them against a know good running Tip.

The PST2 can read:

Input signals can be checked and read out with this menu:

- Selector lever position

- Selected gear

- Multi-function switch

- Kick-down switch

- Downshift switch

- Upshift switch

- Manual program switch

- Stop light switch

- Traction Control

The following actual values can be read out with this menu:

- Rpm

- Transmission input speed

- Speed, front right

- Speed, front left

- Speed signal, transmission

- Throttle plate angle

- Transverse acceleration

- Transmission temperature

- Supply voltage

- 1-2 shift, lower rpm range

- 1-2 shift, medium rpm range

- 1-2 shift, upper rpm range

- 2-3 shift, lower rpm range

- 2-3 shift, medium rpm range

- 2-3 shift, upper rpm range

- 3-4 shift, lower rpm range

- 3-4 shift, medium rpm range

- 3-4 shift, upper rpm range

- 4-5 shift, lower rpm range

- 4-5 shift, medium rpm range

- 4-5 shift, upper rpm range

- 5-4 shift, lower rpm range

- 5-4 shift, medium rpm range

- 5-4 shift, upper rpm range

- 2-1 shift, lower rpm range

- 2-1 shift, medium rpm range

- 2-1 shift, upper rpm range

- Map

and

The following drive links can be controlled:

- Solenoid valve 1

- Solenoid valve 2

- Solenoid valve 3

- Coolant shutoff valve

[Izzy]

Scott, looking through the shop manuals, page 37 D10, 11, 12, did you replace the DME or the Tiptronic Module? Two separate controllers (boxes), just in case.

[ScottArizona]

Hey Izzy, my tech informs me (and I confirmed this with Porsche) that in my car the dme and tip control module are intergrated. That is why it is so expensive in my car (apparently later cars got a separate tiptronic control unit that is much less expensive).

I've got the car back now because I wanted to trouble shoot a few things myself (and because my mechanic won't be able to give it any more attention until tuesday given that he is doing race support/prep for some cars that will be running at Phoenix International Raceway this weekend).

One thing I am going to look at are wheel bearings and wheel speed sensors. If a sensor is giving a wrong reading, it might not throw a code, but could be off enough to confuse the tiptronic (its at least worth a shot). I am also going to switch rear tires with my dad's tires to see if I might have an issue with an out of round rim or uneven tire wear (I noticed the insides of my sport contacts are wearing more on the insides) that could be causing the havoc. wish me luck.

[ScottArizona]

Well,

I promised an update so it here it. My mechanic, who I trust a great deal (ex factory premier tech now owner of independent shop with pst2, etc...) has basically ruled out everything he can think of, and has really gone the extra mile checking with various experts around the country to try to pinpoint the problem. Still no codes of any kind but the problem has been getting worse as the pulsing at low rpm is becoming more pronounced and the car has begun shuddering pretty badly at times when I try to accelerate. All the feedback points to some sort of a mechanical problem in the transmission. The problem, however, is that cracking open the tranny to trouble shoot would be pretty expensive and might not ever reveal the problem.

So, the suggestion was to throw in a new transmission. From contacting fellow rennlisters that had tiptronic problems that were similar to mine, a new tranny fixed the issues. Of course, getting a new unit is ridiculously expensive (one dealer actually quoted me 12k just for the transmission!). So, I located a used unit from Silver Star Recylcling in Cal. The thing has 49k and they offer a six month warranty (which was the best I found). They gave me what I consider to be a fair price too: 2700, no core exchange needed.

I don't like the idea of a used unit, but it beats taking out a home equity line of credit to fix my car. The tranny should be here by the end of the week. Keep your fingers crossed for me. Thanks to all who have given their feedback. Scott.

[Richard Hamilton]

....... my tech informs me (and I confirmed this with Porsche) that in my car the dme and tip control module are intergrated........

I'm sure this isn't correct. Check the parts list.

Edit: Now I'm not so sure :unsure: (after looking at the parts lists) - I think I might have engaged my mouth before putting my brain in gear. :(

Edited January 17, 2007 by Richard Hamilton

[Izzy]

It bugs me a little bit too Richard, my 99 Cabrio Tip had two separate boxes. They are bolted together under the folding top carpet area, but have different connectors

This picture shows the area I am talking about, and the you can see two controllers to the right of the hydraulic pump (with the green sticker) and two connectors going to each box, the DME and the Tip module. This is my 99 Tiptronic.

Scott, the price is not bad, I had a $7K replacement here in town, for a rebuilt. Perhaps your mechanic can look at any worn parts of the incoming and replace those parts before mounting.

Edited January 17, 2007 by izzyandsue

[Richard Hamilton]

Izzy

I got (and still am) confused when I looked at the PET.

Mine (May 1998 - DME 5.2.2) has different control modules for DME and Tiptronic. The PET is confusing (to my simple mind anyway) as it shows DME and Tiptronic modules pointing to the same illustration number. All the Tip 996's and Boxsters I have seen (during OBC and cruise retrofits) have had separate modules.

Having said that, I think Scott is taking the right route in changing the transmission.

[Izzy]

You might have been right the first time. Here are sections of the manuals for 99.

Items 2 and 3. This is the same as my 99 picture above. Don't have the PET, but at leas the manual shows separate controllers.

[Richard Hamilton]

Izzy - you can download the PDF version of the PET via the Links tab at the top of the page.

Thanks for confirming that I am not going mad! I should have looked at the manual first.

[Izzy]

Thanks for confirming that I am not going mad!

Sorry man, I can not confirm THAT :D , only that my 99 has a DME and a Tip module. My wife has certified that I AM mad anyways, and incapable of diagnosing other car crazies..... :thumbup:

[ScottArizona]

My mechanic initially thought they were separate too, until he checked the PET. Then when we swapped in the new dme we realized there was not a separate controller. interesting. I'll broach this topic again with him to see if we are not missing something, but I'm pretty sure there is only one unit. I'll keep you all posted. Scott.

[ScottArizona]

O.k. THE CAR IS FIXED. I'm so glad to be back on the road again I can't hardly stand it! Didn't realize how much I love this car. My mechanic put in a good used unit and every single problem and symptom has disappeared. The tranny shifts much smoother and quicker than before, with no groaning, moaning, slipping, surging, or jerking. There was definately something amiss in the old unit. My only regret is that we weren't able to determine what exactly it was given that there were no transmission codes and everything the shop checked was healthy. My personal belief is that the other shop that did my atf change 5k miles ago underfilled it by about a liter and that overtime the thing just got cooked, and by the time I noticed an appreciable decline in performance it was too late.

All in all I paid 2800 for the tranny and 1600 in labor and extra parts (updated rms, etc...), which included over $300 in atf alone (a couple total fluid flushes and refills can really add up, but I didn't want to change the transmission without at least verifying that it wasn't a fluid problem). I am very happy with the service I recieved and would not hesitate to recommend Robert at Redline Motorsports in Tempe, Arizona (how many times have you been asked if you believed a labor charge was "fair" before making the payment...that is the kind of shop Robert runs!).

My only question now is what I should do with my old tranny? Sell it to someone who needs a core? part it out? Take it apart and see if anything jumps out as obviously wrong? Maybe gut the internals and make a nice flower pot out of the bell housing? I'm open to suggestions! Thanks again for everyone's help.

[eastriver]

very nice!

where did u get the used tranny?

as for the old tranny, polish it, make it coffer table! :)

[ScottArizona]

I bought the tranny from silverstar recycling, located in the sacramento area I believe. I highly recommend them. I shot straight with them with the prices I was quoted from other yards, and the mileages on the other units I was considering, and they decided to beat the other guys' prices. Another important factor was that they didn't require a core exchange, which saved me nearly $200 in shipping.

With regard to the coffee table suggestion for the old unit, I'm not sure putting a daily reminder for me wife of this fiasco in my living room would be a wise choice if I want to keep feeding my porsche habit in the future.