Jump to content

Server Lease Renewal/Software Licenses

Our yearly server lease, software licenses, as well as hardware operating costs, ARE due Dec 6th, 2021. Our current donations have fallen far short of the funds we need to renew. Please remember the RennTech.org community is Member supported so please consider a donation to help...  THANK YOU!

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)

Macan's Speedometer Error


Recommended Posts

Hi guys,

 

Well, I know there's at least half a dozen threads around here about speedometer errors -- many Porsche models have them. Case in point, my 2014 Cayenne Turbo S does show a speed that is 6% over the real speed; it's been established all Cayennes do that from factory, meaning it's clearly on purpose. I guess Porsche is trying to keep those insurance rates from exploding from speeding tickets.

 

However many don't -- case in point, my 997.2 Turbo S is 100% accurate.

 

So I decided to start a thread on the Macan's speedometer error, for those who are wondering if this model inherited the Cayenne's problem or if, given its positioning as a "sports car", Porsche decided to go with the real speed, like in the 997.2.

 

The news is -- they went with the Cayenne strategy. My Macan does show a 6% error too.

 

My extremely friendly dealer did try whatever they could to correct the issue, but, it seems to be built in to the programming of the speedometer display (analog and digitial) at least in the Macan, there's nowhere in PIWIS you can correct it. The only input in the PIWIS that is related to this is the tire size, but my Macan did have the correct tire size in, and even if we tweaked it a bit (essentially lying about the tire size in PIWIS), it wouldn't compensate for the 6% error.

 

Note that the mileage counter is 100% precise -- so there's no negative implication on mileage measurements. This is particularly obvious in a test I did recently where, bu using the Cruise Control, I went for 30 minutes at a steady speed that was displayed in the speedometer as 70mph (and in my GPS as 66mph), but the onboard computer, when calculating the average based on miles/time, correctly showed my average speed as 66mph.

 

They did put in a call to Porsche, I'll keep you guys posted on what the results are. I doubt they will tell the dealer how to fix it (I doubt there's a way other than flashing the on board computer) but I'm curious to see what they say.

 

If you guys can share your experiences in this thread, it would be great -- there might be an off chance somebody will find a way to correct this...

 

 

 

Link to comment
Share on other sites

  • 4 weeks later...

BMW has done this for years, there's even a formula they use to determine whether the error is within their acceptable range (and it's a pretty WIDE range, in excess of 10% IIRC). They claim it's because of European penelties they face if a car ever displays slower than what it's actually going and that includes if the car has aftermarket/oversize wheels.

 

My 993 is spot on, the '10 Cayenne was off by 1 - 2%, I have yet to measure the Macan but will do so promptly.

Link to comment
Share on other sites

  • 7 months later...
  • 1 year later...

My 2015 Macan S is a bit closer at 4.2% fast.  An cruise at 124 kph results in an actual GPS speed of 119 kph.   The indicated fuel consumption was 9.8 L/100km  - actual measured was 9.9 L/100km.  So fuel consumption was reasonably accurate at 1% error probably the error inherent anyway in measuring by usage from full tank to full tank.  

Link to comment
Share on other sites

  • 3 months later...

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.