MagicRat's modification thread - evidence alert
#1
Burning Brakes
Thread Starter
MagicRat's modification thread - evidence alert
Warning. This thread is going to contain data, published by someone (me), with no affiliation to any aftermarket provider. If you are of a superstitious or nervous disposition, then please consider reading no further.
The background: My GTS has an an ongoing minor problem. After it comes to a stop, if I press the brake hard enough to activate the start/stop (or, usually, the little light that says it isn't available right now) the car does a little lift of about 100-150 rpm, like a ghost has pressed the accelerator. This happens only when the engine is warm. It's not the end of the world, but it is kind of annoying.
(Question, as an aside - has anyone else experienced this, or does anyone have any idea what it is?)
Porsche took the car in and re-flashed the ECU and replaced the throttle body under warranty, which didn't help. They also said that because the car has aftermarket headers and cats, the powers at PCGB said they wouldn't investigate any further unless the car was returned to stock and driven for a bit, and the problem was still there.
I like things to work properly, so have decided to do as they asked. The good news is that my tuning shop now has a dyno, so we get to turn a problem into a learning opportunity. This Friday I am taking the car there. We're going to do one dyno run with the car as is (Fabspeed sport headers, with 200-cell cats), then put the stock headers back on and run it again. I will then post what we find, and then, hopefully, Porsche will be willing and able to fix the weird revving problem. It predated my fitting the headers, by the way, and is nothing to do with them, but so it goes. My bad for not getting it looked at before I fitted them, so I don't mind spending a few ££ in what is now the name of science.
My butt-dyno said the Fabspeed headers produced a slight gain, but that this gain was greater with PSE on - ie the exhaust flow was increased, so the PSE became a limiting step, which it isn't with the standard headers. I'll be interested to see if I'm right, or if it was simply that the noise was louder.
Can I also please ask that this not turn into another modding vs not modding warranty/legal etc thread. I'm of the school that believes even Porsche build things a) with a bottom line in mind, and b) to fulfil a whole lot of regulations not all of which are to do with my driving pleasure, and I don't feel the need for addtional debate about that. A big welcome, though, to anyone who has themselves modified a Porsche and dynoed it pre- and post. Let the fact-fest commence!
Obviously, in a couple of days...
The background: My GTS has an an ongoing minor problem. After it comes to a stop, if I press the brake hard enough to activate the start/stop (or, usually, the little light that says it isn't available right now) the car does a little lift of about 100-150 rpm, like a ghost has pressed the accelerator. This happens only when the engine is warm. It's not the end of the world, but it is kind of annoying.
(Question, as an aside - has anyone else experienced this, or does anyone have any idea what it is?)
Porsche took the car in and re-flashed the ECU and replaced the throttle body under warranty, which didn't help. They also said that because the car has aftermarket headers and cats, the powers at PCGB said they wouldn't investigate any further unless the car was returned to stock and driven for a bit, and the problem was still there.
I like things to work properly, so have decided to do as they asked. The good news is that my tuning shop now has a dyno, so we get to turn a problem into a learning opportunity. This Friday I am taking the car there. We're going to do one dyno run with the car as is (Fabspeed sport headers, with 200-cell cats), then put the stock headers back on and run it again. I will then post what we find, and then, hopefully, Porsche will be willing and able to fix the weird revving problem. It predated my fitting the headers, by the way, and is nothing to do with them, but so it goes. My bad for not getting it looked at before I fitted them, so I don't mind spending a few ££ in what is now the name of science.
My butt-dyno said the Fabspeed headers produced a slight gain, but that this gain was greater with PSE on - ie the exhaust flow was increased, so the PSE became a limiting step, which it isn't with the standard headers. I'll be interested to see if I'm right, or if it was simply that the noise was louder.
Can I also please ask that this not turn into another modding vs not modding warranty/legal etc thread. I'm of the school that believes even Porsche build things a) with a bottom line in mind, and b) to fulfil a whole lot of regulations not all of which are to do with my driving pleasure, and I don't feel the need for addtional debate about that. A big welcome, though, to anyone who has themselves modified a Porsche and dynoed it pre- and post. Let the fact-fest commence!
Obviously, in a couple of days...
#2
Rennlist Member
you probably want to reset the ECU after you return to the stock system to have it relearn mappings ... but you knew that ...
#4
Burning Brakes
Thread Starter
#5
Rennlist Member
#6
Curious - is your GTS wrapped? Your avatar looks matte to me, cant tell if that's just agate, or a matte paint/wrap.
Edit - found your post about the wrap, looks amazing.
Edit - found your post about the wrap, looks amazing.
Last edited by PatrickC23; 02-10-2016 at 03:50 PM.
#7
Burning Brakes
Thread Starter
Re the ECU I'll ask my tuning guru, but car has already had all adaptations removed and full ECU reset which didn't solve the problem. We shall see!
Trending Topics
#8
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
MagicRat,
Let me know if there is anything we can provide to assist in the testing and resolution of your drivability problem. I look forward to seeing the results and you getting back on the road without any hiccups
Let me know if there is anything we can provide to assist in the testing and resolution of your drivability problem. I look forward to seeing the results and you getting back on the road without any hiccups
__________________
Porsche Performance Specialist
John@Fabspeed.com
215-618-9796
Fabspeed Motorsport USA
155 Commerce Drive Fort Washington, PA 19034
www.Fabspeed.com
Porsche Performance Specialist
John@Fabspeed.com
215-618-9796
Fabspeed Motorsport USA
155 Commerce Drive Fort Washington, PA 19034
www.Fabspeed.com
#10
Drifting
I'm just so grateful the 911 allows the off button to stay pushed when you restart the car. Of course, inexplicably the Sport or Sport+ or PSE buttons don't stay like they were, so I guess having to push one more button EVERY FREAKING TIME I START THE CAR wouldn't be the end of the world.
Seriously, anybody know why Porsche is so certain I won't want to be in Sport+ mode next time I drive, even though I wanted to be in it last time (and 98% of every other time) I drove?
Seriously, anybody know why Porsche is so certain I won't want to be in Sport+ mode next time I drive, even though I wanted to be in it last time (and 98% of every other time) I drove?
#11
Rennlist Member
I'm just so grateful the 911 allows the off button to stay pushed when you restart the car. Of course, inexplicably the Sport or Sport+ or PSE buttons don't stay like they were, so I guess having to push one more button EVERY FREAKING TIME I START THE CAR wouldn't be the end of the world.
Seriously, anybody know why Porsche is so certain I won't want to be in Sport+ mode next time I drive, even though I wanted to be in it last time (and 98% of every other time) I drove?
Seriously, anybody know why Porsche is so certain I won't want to be in Sport+ mode next time I drive, even though I wanted to be in it last time (and 98% of every other time) I drove?
#12
Drifting
But surely the auto stop feature is a contributor to mpg and emissions. Why bother to make it permanent and the others temporary? obviously customer convenience is not the driving decision, so why not eek out every last bit of low emissions and fuel economy that you can?
That's what doesn't make sense.
That's what doesn't make sense.
#14
Rennlist Member
Actually, manufacturers originally got the credit for offering a start/stop system regardless of the programming. That loophole is soon to close and new cars will require you to push the button to turn it off on each ignition cycle.
#15
Pro
Join Date: Feb 2007
Location: My garage, where else?
Posts: 621
Likes: 0
Received 11 Likes
on
5 Posts
I'm just so grateful the 911 allows the off button to stay pushed when you restart the car. Of course, inexplicably the Sport or Sport+ or PSE buttons don't stay like they were, so I guess having to push one more button EVERY FREAKING TIME I START THE CAR wouldn't be the end of the world.
Seriously, anybody know why Porsche is so certain I won't want to be in Sport+ mode next time I drive, even though I wanted to be in it last time (and 98% of every other time) I drove?
Seriously, anybody know why Porsche is so certain I won't want to be in Sport+ mode next time I drive, even though I wanted to be in it last time (and 98% of every other time) I drove?