sputters

I posted this in my new to FE570 thread but thought I might get more eyes on it here. I have a brand new issue. I think it's a fuel issue based on some research and tips from Rainerio on here. About 5 times in a few hours, mostly on downhills in 2nd gear and engine breaking or just...

I had a cold start issue,the dealer took it apart & put in a new injecter. then it started , but wouldnt stay running untill fully hot. He took out the new injecter, & put the old one back in. still wont stay running. he has created this problem but is unable to fix it .It starts right up like...