Pete D

Customer states RPM stays higher than normal during shifting. Scan for codes. ROAD TESTED DURING/COLD OPERATING TEMPS & COULD NOT DUPLICATE CONCERN. SCANNED VEHICLE & NO DTC SET CURRENT/ HISTORY. To the SA's credit he suggested bringing truck back if issue persists. Not sure why they didn't use the word "Throttle" in the service request but I can guess.

Dealer reports " no codes, no problem. " I don't want to tow anything with this throttle hanging open. A few seconds of rev hang I get it. 10 seconds or so is too long.

You may be a winner. Note scanner read out above while idling at 625 rpm. The two accelerator position sensors don't match. ACC POS #D is 18.8 %. ACC POS #E is 9.4 %. GM TSB 07-06-04-019F calls them APP sensors. This TSB addresses accel pedal position sensors (1 and 2) being out of synch. The TSB doesn't apply to 2019 (yet). https://static.nhtsa.gov/odi/tsbs/2017/MC-10139090-9999.pdf And to think I bought a new truck so I wouldn't have to work on it.. dream on.

Thanks Lucas287. I've been thinking it's a programmed emissions reduction strategy. I just noticed the scanner does have gas pedal position also (ACC POS D+E). Interesting. Thanks for the feedback. It will go to the dealer. Pete

My 3 month old 2019 Silverado 5.3 6sp auto throttle does funny stuff on the freeway and descending hills. When I lift off the gas pedal in traffic at speed, the RPMs don't drop for at least an eighth mile. Cruise control on or off, makes no difference. When descending hills, the truck picks up speed rapidly when you lift off the gas due to the "open" throttle.. Even downshifting descending a hill the truck picks up speed rapidly. I find myself on the brakes constantly and unexpectedly to avoid slowing traffic ahead. To confirm I wasn't losing my mind, I data logged the throttle position sensor while driving extensively. It normally reads 14% absolute at idle and cruise with no pedal pressure. Lifting off the gas on the freeway in high gear the TPS drops down to 21% for about 10 seconds then goes down slowly to 14%. The 14% feels fine, don't notice additional throttle. Each time you touch and release the throttle it does the slow return to idle thing. It's that 10 seconds or so of 21% unintended part throttle that's driving me crazy. Any ideas? Thanks, Pete