Life threatening safety problem: while merging into high-speed traffic on [xxx] in charlotte nc, my 2010 gmc sierra rapidly decelerated from approximately 65 mph to 10 mph. two tractor-trailer trucks going at least 70 mph narrowly avoided rear-ending me . only the lack of traffic on there right side prevented a major disaster. my dashboard showed a engine power is reduced/service traction control/service sabilitrak warnings, and the engine idled erratically as i maneuvered off the to the side of the highway. there was no throttle response. this engineer design put the safety and lives of many at risk by dumping engine power to what is the equivalent of slamming on the breaks at high speed without warning. in april 2018, approximately 8 months ago, i had the exact same problem while driving in my neighborhood road. an authorized dealer completed a $679 replacement of my throttle-body gasket and gas pedal assembly (see attached receipt). the truck drove without issue until this incident. i didn't think this was a serious safety issue because it did not happen at high speed. now, i have the same problem occurring at a high rate of speed on the highway. finally, the dealer explains that there are multiple issues that can cause this malfunction and they are now completing another $600+ repair, replacing multiple parts (repair bill not yet available). based on this troubleshooting and repair history, a consumer is never getting a guaranteed permanent fix for this problem. this begs the obvious question, of why is there a designed malfunction that jeopardizes safety in this manner? parts of this document have been redacted to protect personally identifiable information pursuant to the freedom of information act (foia), 5 u.s.c. 552(b)(6).