I recently had work done on my car because the speed sensor was bad, and I had a funky idle. The car would jump up to like 3000 rpm and then drop slightly but rev up and down over and over. Anyway, I got it fixed and it turns out the intake manifold gasket was cracked and it was causing a leak (this is because my friend who is a mechanic was replacing my egr and cleaning my intake manifold and then accidentally cracked the gasket but was able to seal it up with some pasty solution stuff). Idle issues are now gone, but apparently the mechanics did some shoddy work because a day later I noticed my car starting to overheat and after parking, I noticed coolant dripping from one of the ends of my upper radiator hose. Turns out the clamp on the hose was loose and the hose itself wasn't even 100% on. After tightening the clamp and fixing the hose, there was no more leaking and I added coolant. The car has been fine, however, it will occasionally and randomly get a little hot. The temp gauge never leaves the line before the middle, but sometimes it flirts with getting to that middle line and will sometimes even line up perfectly with it, but it never goes higher. Some side notes, the only other overheating problems I have ever had were when my water pump was leaking and I ended up replacing the water pump, timing belt, and radiator altogether. This was just under a year ago so those parts are pretty new. And just before that, I changed the EGR valve and cleaned out all the build up in the pipe and intake manifold. Yet, my CEL is on telling me its the EGR again. What on earth is causing the car to slightly overheat??