Hyundai 2.4L GDI engine. 87K miles
I hear this Rattling sound between 2600 and 2800 rpm. Otherwise car runs very smooth.
I'm thinking the Direct Injection High Pressure fuel pump is making the rattling sound but could be wrong. Need to ask the wife to rev up the engine and check. Seems to be coming from the top of the engine right where the pump is located.
It has been cold(er) lately maybe 27°F
don't laugh please
I think the noise started when it got colder but maybe something else other than the pump is causing it.
I also have another question.
I have always had the engine cover off. The cover has a hole that fits right over the High pres pump and is fully insulated all around the pump and covers it like a blanket . iirc, when I had touched the pump in the summer, it was relatively hot but when I touched it yesterday after getting off the freeway it was cold. I just put the engine cover back on. I was thinking the cover and the insulation is to suppress engine noise and the ticking noise but maybe the High pressure pump needs to retain some heat!? idk