General Bad MAS/ECU?

[mac 108]

I have a sputtering problem at high RPMs with my AWD turbo automatic. I was looking at a log I made the other night. I know that the Palm logging software is limited to logging up to 1600 Hz. At high RPMs the log records MAS readings of 900+ Hz, then after that, the values are "#######." This leads me to believe that I have a MAS/ECU problem. I think I need to go ahead and setup my 2g MAS and see if that cures my problem, but I do suspect a screwy ECU.

 

[dsm-onster]

I have a sputtering problem at high RPMs with my AWD turbo automatic. I was looking at a log I made the other night. I know that the Palm logging software is limited to logging up to 1600 Hz. At high RPMs the log records MAS readings of 900+ Hz, then after that, the values are "#######." This leads me to believe that I have a MAS/ECU problem. I think I need to go ahead and setup my 2g MAS and see if that cures my problem, but I do suspect a screwy ECU.

What boost are you running? Are you running your 650s now? SAFC or MAFT? what is your fuel control?

If you're running anything over 15 psi and running a piggy back w/ the 650s, then I strongly believe that you're getting 1g maf overrun...

 

[mac 108]

15 psi, SAFC II, 650cc, Walbro 255, Aeromotive AFPR

 

[dsm-onster]

Well it is entirely possible that you are overruning your 1g maf... Usually this happens at higher hertz numbers but remember that you are reading lower hertz numbers than the maf is actually putting out because of your airflow compensation for injectors that are so much larger than stock...

So it is entirely possible that everything is just fine. Swap in the 2g maf and tune that. I think it puts out 10% less hertz for the same airflow. So tune your base settings as if you're running 580cc or so injectors.