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907DAVE
Sun, February 28th, 2010, 05:52 AM
In a previous set of programs I was running the cruise control was very jerky, it would accelerate hard and back off hard, it was so bad I never used it.

They only thing I found that would soften this was to lower ICP in my cruise RPM/MFD range. I think this was hurting my economy, which defeats the purpose of cruise control altogether.

With my new injectors I am concerned that this issue will be much worse because of the higher ICP required for proper atomization(big nozzles).

What other adjustments can be made to get the cruise control............... under control?:)

cleatus12r
Sun, February 28th, 2010, 10:47 AM
HA HA!

A few things that have effect on the jerky, on/off cruise control......

PW multiplier with too much "spread" between ICP ranges (y-axis)
Low boost fuel. Again, not gradual enough.
MFD/Inferred relationship. If the range in which you're "cruising" happens to fall into an area where the MFD is high/low (like a non-linear APP) where there is virtually nothing for the first 1/4" of pedal travel, all of a sudden it shoots off like a rocket, then tapers off past half way, there can be issues. This is made worse when the inferred throttle position is trying to control the MFD through this "touchy" pedal.


I hope this helps a bit and makes a little bit of sense. I am combining the jerking/sputtering while going down hills and the on/off cruise control. The worst was my previous tuner's programs while going up and down little rolling hills (10 or so feet of elevation change about 200 yards apart. My brother ran some programming that caused everyone in the truck to "head bang" at a frequency of about 3 Hz when driving down some of these 6-7% grades around here with the cruise control on.

Believe it or not, the manual transmission MFD map (that I sent you) took care of a lot of issues without any other changes.