Need a little help from you guys....
07-14-2003, 05:27 PM
#1
AudiWorld Super User
Thread Starter
Join Date: Jun 2001
Posts: 6,555
Likes: 0
Received 0 Likes
on
0 Posts
Need a little help from you guys....
A friend of mine is having issues with his car..
Hes running a K04 with APR software and this is what I think is causing the problem. When the car warms up, at WOT the car really bucks down and will do it like a semi-automatic. ;-/
Hes holding like 25lbs of boost. Almost all the time when hes on it the car literally snaps back down. Its not a studder and it feels nothing like a misfire, its a really hard snap back and it will do it over and over again rapidly.
At first he thought it was the ignition amp but I would think that if it was solely an ignition problem it would feel more like a studder than what it feels like.
I know APR's (Stage 1 ??) software isnt meant to be holding 25lbs, especially with a K04 but could this overboost cause the car to jump down terribly if the software cant accomodate?
Hes running a K04 with APR software and this is what I think is causing the problem. When the car warms up, at WOT the car really bucks down and will do it like a semi-automatic. ;-/
Hes holding like 25lbs of boost. Almost all the time when hes on it the car literally snaps back down. Its not a studder and it feels nothing like a misfire, its a really hard snap back and it will do it over and over again rapidly.
At first he thought it was the ignition amp but I would think that if it was solely an ignition problem it would feel more like a studder than what it feels like.
I know APR's (Stage 1 ??) software isnt meant to be holding 25lbs, especially with a K04 but could this overboost cause the car to jump down terribly if the software cant accomodate?
07-15-2003, 06:24 AM
#7
Elder Member
Join Date: Sep 2002
Posts: 14,366
Likes: 0
Received 0 Likes
on
0 Posts
Right now you are fighting 4 issues.
1. 25psi is well over the boost sensor limit and this will cause the ecu to shut the throttle body once your over 21psi.
2. Chip requested boost is much lower then the actual boost reading so the ecu is getting very confused.
3. Your well out of the fuel range that the K03 chip is designed for so you might be running the injectors at 100% and running the car lean once you get 25psi and enough air flow. Even if the K04 was running at the same boost level as the K03 chip is tuned for you would still be pushing more air flow into the motor so the injectors are running at a higher level even at that point.
4. You could also be hitting the tq limiter that is set inside the K03 chip since your running 25psi which will increase the tq alot over the 1.1 bar K03 chip.
You guys need to wake up and get a real chip that is tuned for the K04 before you do some real damage by running it lean all the time. It is also the only way to get around all of these issues. Going with a EBC or MBC will not help since you will just end up losing the mid range power.
2. Chip requested boost is much lower then the actual boost reading so the ecu is getting very confused.
3. Your well out of the fuel range that the K03 chip is designed for so you might be running the injectors at 100% and running the car lean once you get 25psi and enough air flow. Even if the K04 was running at the same boost level as the K03 chip is tuned for you would still be pushing more air flow into the motor so the injectors are running at a higher level even at that point.
4. You could also be hitting the tq limiter that is set inside the K03 chip since your running 25psi which will increase the tq alot over the 1.1 bar K03 chip.
You guys need to wake up and get a real chip that is tuned for the K04 before you do some real damage by running it lean all the time. It is also the only way to get around all of these issues. Going with a EBC or MBC will not help since you will just end up losing the mid range power.
Trending Topics
07-15-2003, 06:28 AM
#8
Elder Member
Join Date: Sep 2002
Posts: 14,366
Likes: 0
Received 0 Likes
on
0 Posts
Could also be that he is hitting the limit of the injectors.
The K04 running at 25psi is going to push too much air flow for the stock injectors at 4 bar to handle. Even the K04's on the 2000 running at 27psi are running the stock 270cc injectors at their limit while tuned for a 5 bar. Now if it is a non dbw the injectors are not even going to supply enough fuel on a 4 bar for 1 bar of boost for the K04 since the injectors pulse has a limit of about 18.36ms.
