My 2007 Toyota Sienna was in the shop for plugs to be put in. This was on the 10th of Dec. I got the van back same day, abt 3 pm. I live about 2 miles away. I had to use the van on the 11th of Dec. My son and I had Dr appts, I met him at the bowling alley, we ate lunch then ran another errand. on the way back, I called Mike from the service dept and told him my car wasn't idling right. We made an appt to take it back to the shop on the 12th at 8 am Dec 2015. Next the check engine light came on, i called and asked if it was safe to drive van or take it in. Chris told me to go ahead and go to the Dr appt. we never made it. Made it to OH almost to exit 6 when i had to get off the road due to smoking and noises made under the hood. Van shut down, smoking and my son saw that the antifreeze cap wasn't put back on. A state trooper happened to be on the other side of the road, i waved him over as i was on the line with C&C to get help. . The service dept says i put 'stop leak' in my van, which i never did. i am without a vehicle now. Engine locked up. engine failure. my guess is b/c it wasnt getting antifreeze to the engine with the cap off, all the antifreeze spewed all over under the hood of van. There was NO fluid trial behind van, state trooper told me. fluids hit engine, evaporated. I have been a customer of this company for yrs. Human error is at fault here, not fault of mine.