Guys,
My overboost isnt working right.
sport mode on. slam the gas abruplty, nothing happens. the Up arrow doesnt show up on the screen. However, if i slam on the gas, release, then slam again, i overboost to 18 psi for about 2-3 seconds then the arrow disappears and the car is back at 14-15 lbs. what the hell could cause it to run like this ? i have no boost leak. car has an apr flash.



i thought overboost turns on when the gas is pressed down rapidly. i have to do it twice and it only works for a second or two. wtf ?

 

That seems odd....You have any CEL codes? Can you try flashing back to stock and see if this still occurs? One way to eliminate any issues with tune... Not familiar with APR tune, so maybe a dumb suggestion..

Good luck!
DC

 

What gear where you in when you mashed the pedal? Try a rolling "mash" in 3rd or 4th gear and see if you get the same results. If it is a problem, I'd suspect the tune if you didn't find any boost leaks. Let us know.

 

No Cels, no error codes. no sputtering. the car holds 1 bar no problem.

3rd, 4th, 5th, and 6th. its so bizzare (all between 2500-3000rpm, which is right in the middle of overboost range) i had a boost leak by the throttle body. took care of it, ran another boost leak test. no problem. driver side intercooler was leaking. fixed it. checked it. no problem.

the car has been getting pretty bad MPG on the highway (about 20-21mpg vs high 20s). ive datalogged the crap out of it. EVERYTHING reads normal. egts, lambda, air fuel. EVERYTHING.


i replaced the battery two weeks ago.

edit: forgot to mention, there was a hairline crack on the passenger side header which was also taken care of. so theres absolutely no loss of pressure anywhere on the system. the car pulls fine. no sputtering no misfires.

the spark plugs havent been changed since i got the car, and i put about 12k miles on her since april.


i cant figure this out and its bugging the hell out of me.

 

I just got off the phone with APR. They suggested i go to any apr dealer and reflash the car. the file may be corrupt.


i dont know what that means. how does a file become corrupt ? did my ECU download **** and get hit with a virus ?
can someone explain this to me ?

 

Electrical gremlins - maybe something to do with replacing the battery two weeks ago - a mystery.

 

JH, ive had this issue for a few months now.
why do you guys think im getting such bad gas mileage ?

 

Hi There...This is what I was suggesting, and to try and reload the stock flash. I would say that files/tune can become corrupt in a similar fashion to your PC or smart phone etc.. If something is being read, or written and has an interrupt in power, or does not complete the write function, it becomes damaged, and perhaps unreadable. Again, like computers, if the power cuts off while a file is writing the bytes are incorrect and it becomes trash...Something like this may have somehow happended to your ECU?

Or...as stated below Gremlins

Good luck getting it straight.

DC

 

thanks DC

does anyone know how to tell if my ecu is bad ? how do i know if i have an electrical issue? or a short etc ?
this is gonna keep me up all night now until i can get my mind around this.

 

Well....Not for sure...But....

Did this issue seem to align with your battery change? It may be possible that something was going on with the DME/ECU and when the battery was disconnected, it failed to complete and is creating the issue? I would not worry too much and just get it re-flashed, which should overwrite all the settings and likely fix your issue.

If not, you can always have the dealer overwrite your DME/ECU with the latest version of OEM software and then it is back to factory default...then get it reflashed. I have done that before too...labor should be 15 minutes, but the stealer will likely try to gouge you for the 1 hour minimum..either way not too expensive...

Good luck!

DC

 

I would change your plugs while you're at it. They don't last long on a modded car. Sharkster had a nice write-up a while back. https://www.6speedonline.com/forums/...97-turbos.html

 

I have apr and the overboost button does nothing but sharpen throttle response and suspension. There is no overboost as boost has already been ramped ip with the chip. I am not even sure the arrow up icon shows up.

I would suggest u use the toggle and reload the stock program and see if u get overboost with that. If it does u r ok.

 

So i went to my apr dealer today. we couldnt get the "porsche engineer" on the phone when i was there....
the shop owner thinks i damaged my ecu. he said that files dont just corrupt themselves. i mentioned that a few months ago i caused a spark from the rear starter, and he thinks that definately toasted the ecu.

he said it would take half a day to read the file, send it to apr and see what they say, and that i have a 10:1 chance that a reflash will do anything...

i uploaded a video for you guys to see.. this sucks ! im gonna try to get out there tomorrow morning to see what happens.

<embed width="440" height="420" type="application/x-shockwave-flash" src="http://v5.tinypic.com/player.swf?file=famnug&s=5"><br><font size="1"><a href="http://tinypic.com/player.php?v=famnug&s=5">Original Video</a> - More videos at <a href="http://tinypic.com">TinyPic</a></font>
as you can see in the video, the overboost light goes on, the car hits 18psi then it cuts off immediately.

 

That really does suck...hope it get resolved. What's a "spark from the rear starter"?

 

i was getting the car tinted. the transmission was out, the cables on the starter were touching the floor. the window tinter asked me to open the window. i put the key in the ignition, opened the window and heard sparks, so i immediately turned the key off. this was at the end of april. it couldnt have been more than a couple of seconds, and nothing seemed to malfuntioning, so i didnt think anything of it. the car started fine, and never had an issue.

the shop owner said thats called "reverse polarity" and that our ecu's are super sensitive etc etc.

i ran my 6.7 60-130 that same night..