So, the "limp mode" thread got me thinking
10-04-2015, 02:58 AM
#1
MBWorld Fanatic!
Thread Starter
So, the "limp mode" thread got me thinking
We have probably all heard stories of shop employees, lot jockeys, detailers, etc. taking customer cars out and hammering on them. If you ever have to leave your car with someone and are worried about this I can give you an easy way to detune your TT V12 by about 200 HP (not sure if it works on the supercharged motors). It will not stop them from joyriding it, but at least it will be slow so they won't be able to really abuse it.
There are 4 MAP sensors on the v12, two are in the airboxes and measure vacuum/resistance to airflow through the filter. The other two are upstream and downstream of the throttle body and read both vacuum and boost. Before I got my car, someone had replaced the upstream boost sensor which is attached to the passenger side intercooler via a hose, with one designed to go in an airbox. These are the sensors available from NAPA or Autozone and are identical in appearance and wire pulg to the correct sensor. With one of the airbox sensors in the upstream or downstream position, your car only makes 2-3 #'s of boost. It will run perfect, and will not throw any DTC's, it will just be down about 200 HP/Tq, taking all the fun out of joyriding your baby.
IT IS VERY IMPORTANT that if you want to detune your car with this method that you get a new vacuum hose and disconnect your sensors hose from the intercooler, rather than try to remove the sensor from the hose. You will break the sensor every time you try to remove it from the hose, so keep the hose attached to the sensor and just get another hose along with the airbox sensor.
I hit a pothole so bad it bent a wheel Monday and after that I need to get my alignment checked. I will be taking my car to a friends shop to get this done so I don't have to worry about them driving my car. But, not everyone has a good friend with an alignment rack and some of you may be stuck leaving your car with a shop or dealership you don't trust completely for some kind of service.
For about $50 and 10 minutes of your time you can take all the fun out of joyriding your monster. Not sure if anyone cares, but thought I'd throw this out there.
There are 4 MAP sensors on the v12, two are in the airboxes and measure vacuum/resistance to airflow through the filter. The other two are upstream and downstream of the throttle body and read both vacuum and boost. Before I got my car, someone had replaced the upstream boost sensor which is attached to the passenger side intercooler via a hose, with one designed to go in an airbox. These are the sensors available from NAPA or Autozone and are identical in appearance and wire pulg to the correct sensor. With one of the airbox sensors in the upstream or downstream position, your car only makes 2-3 #'s of boost. It will run perfect, and will not throw any DTC's, it will just be down about 200 HP/Tq, taking all the fun out of joyriding your baby.
IT IS VERY IMPORTANT that if you want to detune your car with this method that you get a new vacuum hose and disconnect your sensors hose from the intercooler, rather than try to remove the sensor from the hose. You will break the sensor every time you try to remove it from the hose, so keep the hose attached to the sensor and just get another hose along with the airbox sensor.
I hit a pothole so bad it bent a wheel Monday and after that I need to get my alignment checked. I will be taking my car to a friends shop to get this done so I don't have to worry about them driving my car. But, not everyone has a good friend with an alignment rack and some of you may be stuck leaving your car with a shop or dealership you don't trust completely for some kind of service.
For about $50 and 10 minutes of your time you can take all the fun out of joyriding your monster. Not sure if anyone cares, but thought I'd throw this out there.
