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Forum nameEngine Management Systems & Controllers
Topic subjectMS2 boost dropping above 6k rpms
Topic URLhttp://forums.2gnt.com/dcboard.php?az=show_topic&forum=54&topic_id=5592&mesg_id=5592
5592, MS2 boost dropping above 6k rpms
Posted by SilvrEclips, Dec-31-69 06:00 PM
Recently I sold my MS1 unit and started clean with a new MS2 unit I assembled. Unit has worked flawless until I started to really tuning boost portions of the map. Here a run down on the board

MS2 v3.0 running gslender v2.8 firmware. (also tried 3.2.1)
IAC mods
Launch control
Fan control
Meth injection
Boost control
Tach output

The issue is that during a pull, the map sensor gets noisy as boost builds. Its set to around 10-12psi, but as soon as I get to 6k boost drops down to about 8-9psi and just floats around there. So far I have tested the following things:

-Confimed boost reading with 2 mechanical gauges (boost is not dropping off only MS claims it is.)
-Changed to a different map sensor
-Added a resistor pack to injectors to run them as High Z
-Grounded the ignitors outside the board on their own ground
-Tried grounding MS to engine block, battery, cleaning the existing ground
-Tried running a separate 5v reg just for the map sensor
-Tried unplugging the VSS and tps and any board mods that run off the 5v proto area.
-Checked over the map circuits to verify good connections on the board with a DMM


Its so weird bc its happens EXACTly at 6k everytime. At part throttle out of boost above 6k its fine, but as soon as I hit the gas hard and boost builds it goes crazy. I tried replicating conditions on the stim with no success.


The only thing I have seen that is weird is the 5v reg voltage increases as boost/rpms increase. Here a vid of the DMM checking voltage from the 5v proto area at partial throttle and then hitting the gas. You can see how boost causing the voltage to increase to almost 5.1v. The second video is showing the mech boost gauge VS tunerstudio and the map dropping out.

This issue is driving me crazy and I have no idea where to look/check next. Any help is much appreciated.

http://s189.photobucket.com/albums/z173/SilvrEclipse/?action=view¤t=VIDEO0006.mp4

http://s189.photobucket.com/albums/z173/SilvrEclipse/?action=view¤t=GOPR0024.mp4

Ill post a log in a bit

Log - http://www.2shared.com/file/FK3-DT6w/Drive2.html

MSQ - http://www.2shared.com/file/7queOeSj/Eclipse_rev2.html
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