RE: Tune "fades" with time?
 

Thanks guys, this is good stuff.

RE: Tune "fades" with time?
 

My Brenspeed tune recently "faded"...I did the gas pedal trick which starts the memory anew and the tune is back!

RE: Tune "fades" with time?
 

I'm running the Bren SCT tune and have not felt any loss or change in power or throttle response since loading it. The one thing I have noticed, is the bad MPG. I don't drive it much on the highway and it gets about 13.5 to 14.5. I'm thinking it has the adaptive learning turned off, otherwise I think I would have noticed a change or loss of power by now (the tune has been loaded now for several months).

RE: Tune "fades" with time?
 

Sorry, I know that sounds a little weird but the biggest thing here is what you are feeling is a totally different area then what the adaptive learning controlls.

The adaptive learning feature in the PCM learns and corrects fuel trims, this in turn helps to keep milage in check. When you get to a pedal position that is enough to make reasonable power then you should be in Open loop and then the fuel trims, or adaptive learning, is off completely anyway.

Now, this is my THEORY on what you guys are feeling. What you are feeling is the PCM learning throttle tables and adjustments and on the auto's learning transmission pressures and slip times.There again this has nothing to do with what is referred to as Adaptive learning.

The way I combat that is to completely remap the DBW tables, not one but a few different ones, and this in turn gives the PCM a different table to adapt from and learn to and this will keep the throttle crisp and alot better then factory. There are SCT dealers that dont have access to this table and SCT basefiles do some changes but not the ones I speak of. Diablosport make nearly the same changes as SCT base files to the throttle tables.

Now as for the automatic features there is a few ways to combat this as well, basically doing the same thing by adjusting different tables, times, and rates you give the PCM a new base to learn from and hopefully not try to reduce. There are also a few switch positions that need to be changed but without going into great detail I'll leave it at that.

Basically to help get around this you should start with a custom tune from a custom tuning dealer with a good rep and that will provide you with support after the sale should you need it. Not some warehouse dealer that pushes them out the door with free overnight shipping or a new shop that wants to save you $20 by buying from them over a reputable dealer.

RE: Tune "fades" with time?
 

Thanks for that second post Doug. It really helped, particularly the above quoted sentence. I think I kind of get it - the car still "learns" after a custom tune. but the baseline from which it starts from and compares is altered and thus better. I know it aint that simple, but it makes sense to me now, so hopefully I'm not too far off. Thanks for indulging me. I think your willingness to post here just to help someone exemplifies the excellent customer service many of your customers have mentioned. When the time comes, I'll be sending my business your way.

And, no - I was not paid to say that. :)

RE: Tune "fades" with time?
 

Is this true for 5 speeds as well? I got a dyno tune from a reputable SCT tuner and the car was a scary monster the first week. I drive it maybe a50-75 miles a week tops in fair weather. Right after getting the tune, I managed a 13.6 on street tires at the track over and over with 2.20 60fts. I couldn't wait to get the drag tires on the next time.

Yesterday, at the track, I got in 13 runs and the car was a dog. I even on the ET Streets and hooked pretty good (consistent 1.9 60 fts), but struggled and only got in two 13.6 runs, and most were 13.9-14.2.

I know there are lots of factors that can account for performance at the track, but I put the street tires back on the rear today, drove the car around, and I swear the "oomph" factor was gone. I mean GONE.

With the SCT tuner, can you just upload the tune over and over to keep the tune "fresh"? Do you have to bring it back to the stock tune first, or can you continually overwrite it?

John

RE: Tune "fades" with time?
 

I know that Doug knows this stuff better than me so I am going with what he said in that there are other ways the car "learns" or at least looks at data so just by shutting the adaptive learning off the cars computer still has things it looks at. And you are right, many factors add into why you ran the times you did. I think you get used to the tune after a while. Switch back to the stock tune and see if there is any difference;). And no you do not have to reload stock tune you can reload a different preformance tune right over the one that was in there.

RE: Tune "fades" with time?
 

LOL..Never in a million years! My car would never forgive me...

John

RE: Tune "fades" with time?
 

I had my battery disconnected when installing my shift light, and when everything was hooked up and I took it for a test run, I could swear it felt as though it had more power. Not just until it warmed up either, even after driving it for 20-30 mins. I really didn't think much about it at the time, but after reading this post, it makes me think it did. Iwill begoing to the track this weekend, I will make a few passes as is and then disconnect the battery for a while and make a few more and see if my #'schange any. I will let you know the outcome.

RE: Tune "fades" with time?
 

whats the "gas pedal trick"?