turbotuner20v

If I take out my stock '09 ECM w/ 2,900 miles and put in a new blank ECM and have it VIN matched/tuned/ect. and run it for a few thousand miles and switch back to the stock ECM, do I need to do anything different at that point besides just plug and unplug the two? There are no calibrations that need to be done when swapping back and forth and no error codes or weird issues that will pop up?

I'd like to clean up my a/f tune so that the car has better driveability w/ my mods, but I'd like to use the stock ECU when running the car hard to keep it conservative.

I just want to make sure after the initial calibration of the new ECU I can swap back and forth w/o needing any calibration and that it doesn't brand the ECU with a time/date/mileage stamp when it's removed and reinstalled.

Motorhead-47

"Clutch Pedal Position Learn" bit me trying to do that very thing on my 2009 MN6. Wanna buy a slightly handled but never fired up ECU?...

Oh and no "clutch pedal position learn" means no start FYI. HP tuners has a button for this function but it never worked for me.

turbotuner20v

bummer, so even though it learned the clutch pedal position when the car left the factory, unplugging it and plugging it back in causes it to lose that memory?

Motorhead-47

Let me clarify to make sure we are on the same sheet of music. I bought a second ECU over a year ago for my 2009 when this whole rampant warranty crap started. The plan...at the time...was to use this new backup ECU with a 100% factory stock tune if I ever needed it for warranty work. When I plugged it in and finished the security learn it would not spin over. Got the "clutch pedal position learn" code. I went back and forth with HP Tuners and although they claimed the function works I was never able to clear that code on my car and never used that ECU. I was able to plug the original ECU back in and it worked fine. I'm sure someone with a Tec2 or maybe even EFILive can resolve this for me but I've mod'd a wee bit too far to even attempt a drivetrain warranty any longer. The unused E38 ECU sits on my desk...nice paperweight.

The "clutch pedal position learn" has to be accomplished with the ECU installed in the car. From what I've been told the sensor changed from a simple off/on function to some sort of linear/rheostat switch in 2009. I suspect, but don't know for sure that HP tuners has that function working in pre-2009 cars and assumed it would be the same in 2009 and up. For me, it was a no-go and I've never found the HP Tuners folks to be that responsive to customer queries so I just...gave up and put it on the shelf.

If you get your ECU programmed at the stealership and get them to start your car with it you'll be good to go I would think.

turbotuner20v

Ok, that sounds like it will work then...

I have a 100% stock ECU in my car now that came with the car when I bought it new.

I'm buying a 2nd ECU and having my tuner use their Tech II to match it to my car and tune it. (sounds like this should take care of the issue you had)

Now I'll have 2 ECU's that can be swapped in and out of the car at will w/o any calibration or relearning/reprograming needed. The 100% stock, original ECU that came with the car.. then the tuned ECU I bought separate.

Does that sound right?

Motorhead-47

You should be fine.

mikefili

I did the 2 ECU thing with my 09, put the OEM ECU on a shelf in the garage with the intent of switching it out if needed, well G.M. located the unit at the highest point in the right front fender, much higher than in prior years, so high that it is almost impossiable to change, I went to a very well respected Corvette shop to try to have them switch the two units, they said the only way to get at it is to remove the fender. When I sold the car instead of switching out the ECu's I just reflashed the 2nd ECU with my EFI Live to save the crazy hard job. Now I have the OEM ECU that came with the car. Anyone need or want to buy it?

turbotuner20v

how hard is it to remove the fender?

Motorhead-47

You don't need to remove the fender to swap an ECU. I've done it several times in my 09' without issue.

turbotuner20v

Cool... I'm pretty handy around the car, so hopefully it won't be that hard working blind up in that area

mikefili

I am sorry if I was not clear, I did not ever remove the fender, I was stating that a shop wanted to do that to change the ECM for me. I did infact change the ECM once to the reprogramed one and did not want to do it a 2nd time. I would think that it would have been much easier with the car on a lift, I did it on my back with the car up on jack stands.

Motorhead-47

As long as you are not a dwarf you should be able to reach it. I think I used a 1/4" drive rachet with a 10mm socket...2 bolts. Once it's loose they ECU will swing around on the connectors/wire bundles allowing you to lower it to about bottom of the car height to unplug the two connectors. 5 minute job if the right front corner of the car is jacked up.