Can an OBD scanner help me discover a 996's history?

[roadcraft]

Hello kind people,

This is my first post here, but I've been lurking for a little while and am extremely impressed by the great "signal-to-noise" ratio and the generous contributions of some very knowledgable people.

I'm about to take the plunge into 911 ownership, with a Mk.I GT3. Having made this momentous decision a short while ago, I've been doing much research to try and get a really good understanding of the car and the various options, and increase my chances of getting the best possible car. I've seen comments referring (loosely) to the possibility of dealers etc being able to tell how a car has been treated by interrogating the ECU or other onboard electronics.

Does anyone know more about the specifics of this? I've had a look at the OBD pages on renntech.org, but the codes all seem to refer to broken sensors and various such things that would cause the check-engine light to come on, rather than mentioning any useful stuff like "true total mileage", "number of times red line has been hit", "total knock sensor activations" or "number of minutes spent at full throttle". Am I barking up the wrong tree, or is just unconfirmed hearsay that even the OPCs can do this?

Thanks in advance,

Michael

[phelix]

An OBD scan tool will only send the codes to the ECU that will return the data fields defined by the OBD protocol which is generic across multiple marques. For what you're after you need the Porsche System Tester which I think is over £2K. I'm not aware that anyone has cracked the Porsche codes yet whereas there's the VAG COM tool for Audi/VW et al and carsoft for BMW and Mercedes.

[Raven Flyer]

Micheal

I used to have an official Subaru diagnostic unit (called a Select Monitor) which would show everything the ECU held. You had current error codes and stored error codes. Stored error codes were problems that the ECU had encountered but which had then gone away. New TVRs have full factory datalogging (careful how you run them in chaps), but Porsche do not.

From reading your post, you seem to be looking for a Porsche that has not been driven fast.

I have to ask you... why do you want own a Porsche? Is it to drive fast? Is it to enjoy the way is rises up the rev range with a surge of excitment? Is it to us its potential to indulge in the road that lies ahead of you?

Do you really think that you will find one that has not been bought, by the previous owner, for *exactly* the same reasons?

The cars are made for it. Buy one, enjoy it.

[cyrus1971]

One important learning is that number of hours the engine has been running. Compare this to mileage reading and you can get a feel for the type of driving a car may have done. Motorway vs. racetrack – high motorway miles etc. It’s a useful cross check and relevant if you fancy a GT3.

I took a private sellers 996 to a specialist and paid £200+ VAT for a mornings worth of complete inspection including that check. Money well spent because it exposed an issue and I walked from the deal. Got an OPC 996TT instead.

Good hunting.

[roadcraft]

Hi Phelix and Cyrus,

So it seems possible that if I took the car to an OPC for warranty approval, they could check this aspect out while they were about it. Cool, I'll have a word when I book it in. Thanks.

Raven, thanks for your comments too. In response, I think there's a difference between a car that's been driven fast but with a semblance of mechanical sympathy and one that has been thrashed mercilessly or spent a significant portion of its mileage out on track. With a GT3 there's a strongish possibility of the latter. In the worst case, a number track car hire operations have GT3s on their books and I would be keen to avoid becoming the next owner of one of those, no matter how well it seemed to hang together on the test drive.

M