I'm considering buying a new ecu instead of flashing my stock one. This way i can swap the flashed and stock one at any time. Just wondering though... do the ECU's keep track of miles driven? If they did, then swapping them might cause suspicion when taking the car to a dealer.

 

I did this . . . complete waste of money for me. I never once switched ECUs and my original ECU has simply gathered dust in my garage for years.

The ECU records one or more parameters that Porsche techs can cross-reference to establish that you have swapped ECUs, including most importantly, engine hours.

If you are set on buying a second ECU, you can buy mine.

Craig

 

thanks for the input. I guess theres no point then...

The reason I had asked was because I'm considering an extended warranty. But after flashing the ecu, I'm guessing all engine related claims will be thrown out the window huh?

 

I think that depends on which tuners software you use. Some can be detected while others can't.

 

Yeah I have seen some tuners mention that their software is undetectable. Has anyone actually confirmed this?

 

If you decide to get another ecu and it has been in a car before, you must get the programming codes from the vehicle it came from. Otherwise it will be useless, unless of course, you are a dust collector like Craig.

 

what parameters would reveal that a ecu has been switched? I can understand the engine hours if the stock ecu was replaced when the car was new. But if you've already logged alot of miles on your stock ecu, I'd think engine hours would be irrelevant. Now if somehow the ecu's stored the # of miles that have been driven, that'd be a very good indication of a swap... but I've had several sources tell me that there is no such recording.

 

The ecu it self does not store mileage.

There are a few things that are stored in an ecu that make a chipped/flashed ecu detectable by the dealer.
First, all me7 ecu’s have a flash counter. If this flash counter is unusually high (I would say 3+) the dealer would have a pretty good idea that the ecu is flashed. Most tuners at this point have found this counter and set it to 1 or 0 when they are done flashing.

Second and one that tuners aren’t getting around. Checksums, there are 36 different blocks in there ecu that are summed in some sort of checksum algorithm. Each ecu software number had 36 unique checksums that the factory scan tool at the ability to reference against stock checksums. I know for a fact this is what a regional Audi/VW field rep will look at to see if a car is chipped.

 

thanks nerdhotrod... but my question deals with an entirely replaced ECU. Basically removing the stock ecu and then installing a fresh one with tuner software.

Then anytime one feels its necessary, the ecu's could be swapped back. Would the swap be detectable somehow? Craig mentioned that engine hours could be an indication.. but my stock ecu has already seen enough hours that could corrospond to almost any reasonable number of miles driven

 

Some cars get a DTC when the ecu loses power. This would indicate an ecu swap, but it would also indicate a dead battery at some point in the life of the car....

Realistically...they wont be able to tell if you swap.

 

If a factory rep suspected or was determined to investigate whether the ecu was swapped, I think they would be able to tell from the marks on the nuts, threads on the bolts, etc. (I think the threads are sealed with a colored paint at the factory). Under a microscope, the markings that will be generated from a simple removal and re-install of the ecu will be detctable. That said - if the warranty claim is minor (like a MAF), they would never dig this far, but if you have a major transmission or engine problem, I would be worried about what they may find.

I did the dual ecu thing while under warranty and it worked fine, but I never had a major claim.

 

It would appear as if the battery went dead and that's all. As John said, they may be able to inspect the installation nuts, but that doesn't actually "prove" anything except that the nuts have been removed. There is no label saying "warranty void if removed" so you can remove it out of curiosity, to install a stereo back there, etc.

 

U need to disconnect the battery before u swap the ECUs.... every time u unhook the harness it registers...
You can always put it back to stock when ur selling the car by going back to ur tuner and asking to do so. pure and simple.

 

Hey Mark,

Actually it is safe to remove and replace the ecu without disconnecting the battery. I didn't think so either but this was from a Porsche technician. I saw him do it and no issues.

 

funny because my tech told me that it is detectable so one should disconnect the battery first. ????