An issue?
 

Going down the interstate tonight I decided to use the coast on cruise control. I was slowing down from 75 to 65. When the cc resumed after I released the coast button the tq lock was definately stuttering trying to engauge. I proceeded to try this at some other speeds and the tq lock still stutters to engauge. Stopped at a rest area and put back to level 0 stock problem went away. Its like that hiccup I describe before in that other thread only has been amplified now through cc. I can only get to hiccup through the foot feed from 40-55 mph.

Any suggestions?
Jack?
Bill?

Lars

I know you've probably already checked, but are you SURE your gear ratio is set up properly in your custom options?

Interesting, Lars. I have not felt this problem in my truck at all. However, I rarely reduce speed using the coast button. I usually tap the brake and then reengage once I reach the speed.

I'd try playing with TC lock and unlock points in custom options. I keep coming back to my TC being too eager to unlock under mild load until I reduced the 4th gear lock and unlock points by -10. I also reduced the others by the max amount too.

- Jack

Yes, the gears are set up correctly.

Lars

I forgot this the interesting part is in the com gear pid. The paddlelock flashes on+ off but not the same rate as the stutter.

Here is another discovery with a pid and cc. The accelerator position pid drops to 0% when cc is engaged.

I am going to search for your settings Jack and try them out and or have a chat with Bill early this week tried calling on Friday and new it was hit+miss. So I will try on Monday or Tuesday.

Lars

I don't know how easy it will be to find what I did Lars. However, I reduced the part throttle shift points the max, -2, -3 and -5 for upshift and downshift and I reduced the TC lock/unlock points by the max values too, for each gear

It won't hurt anything to try these, and it may give you a clue what you really need.

- Jack

Thanx Jack!

Lars

im no expert but that seems to be right for the pid to read 0 with CC engaged because it prolly only picks up voltage from the sensor when the pedal is pressed so with cc engaged the cc actuator takes hold to operate everything, meanwhile you take your foot of the pedal and that signal at that sensor is now gone. we had to replace a lot of these units when they first switched to the drive by wire setup for the sensor going bad and causing problems, so this could make sense if im right on how it operates, only a guess though

I just thought it was interesting point to post. I just switched it to engine load pid.

Lars

Except - there are really TWO sensors. There is an Accelerator Position Sensor (AP) AND a Pedal Position Sensor (PP). I think under normal, non-CC conditions, the PP tells the PCM where to place the AP (don't you just love all these initials?). :crazy: Now, I can see that if the CC is on, the PP becomes kind of meaningless, and the AP is controled by the PCM based on speed.

However, note that even with the CC on, if you push down on the pedal, it commands the AP to open, and the truck will speed up, so the PCM is still reading PP in some manner.

I'm puzzled that the AP PID reads zero with CC on too.

- Jack