Engine Hours to Mileage Formula

[BRP]

I have a 2004 Carrera 2 Cabrio with the operating hours counter reading 2596.  Anyone venture what a 14 year average miles/hour would be to determine estimated mileage?  My mechanic says 40MPH low and 60MPH high but that's a big swing.  Car came from the lower Midwest and seems pretty typical for its age, actually shows well.  Had the car 3 months and preventatively replaced RMS, IMS, clutch, struts and full service and after all this.....learned the cluster is not original.  Trying to estimate actual mileage. 

 

Many thanks

 

(Also, anyone heard of a "manipulation dot" in the clock window?  I have a dot there but it's at the top of the window after noon and at the bottom of the window before noon so looks like an AM PM indicator to me.)  

[rockhouse66]

I don't know the right answer to this but I do know that in big city life, mixed with a lot of long highway miles (travelling salesman), 35 MPH was about all I averaged.  (not in a P car - maybe I would have averaged 60 MPH if I had one as a company car)

[Richard Hamilton]

A 2004 996 should record the mileage in the DME (in kilometers), along with operating hours.  You should be able to read this with a PIWIS tester, but I'm not sure if the Durametric will show it or not.

[JFP in PA]

Durametric also shows it.

[BRP]

Thanks for the input but I have a 2002 996 not a 2004 as I said when starting this thread, sorry....stupid typo!!  

The Durametric 20 Software one page printout I have is titled  Bosch Digital Motor Electronics Motronic 7.8 and lists ignitions range 1 & 2, operating hours counter, VIN, data version, type ID DME control unit, order type, country code, trans type and number, and interior equipment, but not miles/kilometer total. Does the PIWIS tester show miles or is there another way to get miles/kilometers out of the DME or am I limited to some kind of average miles per hour assumption?

 

Again, many thanks!! 

[JFP in PA]

4 minutes ago, BRP said:

Thanks for the input but I have a 2002 996 not a 2004 as I said when starting this thread, sorry....stupid typo!!  

The Durametric 20 Software one page printout I have is titled  Bosch Digital Motor Electronics Motronic 7.8 and lists ignitions range 1 & 2, operating hours counter, VIN, data version, type ID DME control unit, order type, country code, trans type and number, and interior equipment, but not miles/kilometer total. Does the PIWIS tester show miles or is there another way to get miles/kilometers out of the DME or am I limited to some kind of average miles per hour assumption?

 

Again, many thanks!! 

 

Both systems show hours, you need to calculate the miles based upon assumed averages.

[Richard Hamilton]

DME7.8 is the same as used in a 2004, so it should show the mileage.  I'm not sure what you mean by "Durametric 20", so it might be an old (or clone) software version.

[binger]

Its a simple formula. Divide the odometer mileage by the operating hours you will have an average MPH.

 

Example: 12,000 Miles / 917 Operating Hours = 13 MPH

Most cars will average between 30 - 50 MPH depending on how much traffic it is driven in so the value of 13 MPH indicates there could be a discrepancy.

[BRP]

To Richard Hamilton above, Durametric 20 was printed at the bottom of the page so I thought it might be a software version.  When I divide odometer mileage (65,000) by engine hours (2600 I get an average of 25 miles per hour over the car's 14 year life.  Knowing this is a replacement cluster I'm trying to get a better estimate of average miles/hour so I can do the math and see what the more likely total mileage is.  In the post from binger, above, using 30-50 MPH my actual mileage would be between 78K (close to my odometer) and 130K (exactly two times my odometer AHHH!!).  Huge difference, trying to get a little better range estimate but may not be able to.  As info I had the car pre-purchase inspected at a Porsche dealer and they did not read or report engine hours, so, I bought the car and put about 5 grand more into it only to now learn the mileage was probably misrepresented with no recourse to the previous owner. 

 

Again, many thanks for all the responses.

[Richard Hamilton]

Of course, it depends very much on the previous owners driving style and location, but in the UK we would reckon that 30mph would be a reasonable average speed.  A heavily tracked GT3 might be higher, and a London-based Tiptronic model somewhat lower.  If you can find someone with a PIWIS, or up to date Durametric Professional local to you, that would be the certain check.  There is a registry of owners in the diagnostic section, and I'm sure any one of them would help.

[Ahsai]

Check out post #48 by Jake Raby http://rennlist.com/forums/996-forum/952397-ln-dual-row-questions-4.html#post13590539