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whackem04
November 17th, 2009, 03:20 PM
What should I look at and what should I log. I have DSP5 but it does it on all the tunes. The surge feels like a fuel surge like if I was going into lope mode, or maybe a sudden surge of air.

LBZoom
November 17th, 2009, 05:32 PM
I would look at your pulse width tables, specifically where any modifications start. Possibly the truck is toggling between a modified cell and an un-modified cell...happened to me once when I made a tune. Maybe look at pressure and base injection tables too, anything to do with fuel, I don't think it's a turbo related issue, wouldn't have that noticeable of an impact. So just be sure to log all the necessary fuel data based on the links on the axis of each table you want to look at. PID's: throttle %, RPM, desired and actual FRP, and commanded fuel during the main injection. Hope this helps man!

Otherwise it could be a fuel pressure regulator, which would probably show up in the log as a difference in actual pressure vs. desired pressure. Do you have a lift pump or anything also?

killerbee
November 21st, 2009, 11:46 PM
log fuel pressure and pulse, as well as vehicle speed.

You will probably see the correlation. If it happens at the same speed, while decelerating, it will be remedied by comparing the operation tables with the "idle mode" tables.

This is not an uncommon tuning mistake.

whackem04
November 23rd, 2009, 01:41 PM
what is the consensus on these?

killerbee
November 23rd, 2009, 01:57 PM
You didn't log fuel pressure and pulse. Just about everything else though. :)

whackem04
December 18th, 2009, 08:36 AM
new log

whackem04
December 28th, 2009, 08:50 AM
Anything?