Cruise control issue

[Justin Kemp]

Sorry for the long post but I want to give as much info as I can about my problem.
2008 Chevrolet Silverado 1500 Z71 6.0L V8 stock Auto trans.
I'm not new to tuning but not a pro by any means. My problem is this. Cruise control doesn't work after tune. I have a mild tune to add a little power. I've adjusted the timing tables and PE tables to be able to actually achieve PE. I've also calibrated my speedo for the size tires I'm running (265/75R16). Once I calibrated the speedo, speedo is correct but cruise is inop. I have a Snap-On Solus Edge also. I can look at my PIDs for cruise control and see the PID readings change when I press any cruise button (on/off, set, and reset). I know the cruise control works properly because I can flash the stock speedo calibration to the ECM and cruise works. It will not work after I calibrate for larger tires. I'm begining to think this is a glitch in the HP Tuners software that needs to be fixed. Anyone have a solution for this problem? I would like to have my speedo be correct and cruise to work. Thanks in advance for any help on this problem.

[mcfarlnd]

I thought I was losing my mind. I?m having the same issue. Immediately after a tune, I?m good but once I turn it off and back on, won?t work. The power light comes on but, will not engage at any speed. I too have modified tires sizes however, I?m also using the custom 2 bar OS.

[ZincGT]

post your tune

[mcfarlnd]

Revisiting this.... I changed my brake switch and it fixed it. I guess because of rewriting the ECU it would clear the problem for a one time use. I was not getting a code but a quick google search, 12.00 amazon part and 10 minutes under the dash, I now have cruise control again.