Hey guys, I ran nitro cars years ago (35 yrs) and really enjoyed it. I recently bought two exceed nitro cars with the vx-18 engine. I set the engines at 3.5 turns off closed and cannot get them to start, or if I do, maintain running. I’ve tried 1/8 of a turn each side of the 3.5, and even 1/4 turn. I’ve also changed glow plugs. I use a rechargeable red cat to heat the plugs, fully charged. Any advice?