i have been hearing a rattling noise coming from the engine under acceleration only. It isn't a super consistent rattle, seems to only happen when accelerating from lower speeds. And sometimes you don't hear and other times you do. It's not a bad rattle or knock it's more of a ticking/light rattling sound that is definitely abnormal. I know my brake accumulator is barking at me and the 3 way coolant valve is going bad as sometimes I get a constant pumping sound. I don't think these have anything to do with it but thought I'd mention it. I went ahead and replaced the water pump and pcv valve as I have 220k miles. The noise didn't go away. Anyone have any insight to this problem?
My engine has a light rattle under cold accelerations too. If its warm is less noisy. If the radio is on you don't hear it. It sounds link valves. All the prius i drove have that same sound. Its only noticeable if you really listen to it. So the prius engine makes a very soft rattle noise when accelerating. If you think your sound is harder, its maybe a exhaust gasket that will rattle also under acceleration. And a question i might think you checkt already......hows you oil level?
Oil level is good, but I am burning oil, and have run it pretty low before on accident awhile ago. Ill check that out and report back. I have had the cat off though and would imagine I would have seen it or changed it since I removed and reinstalled it.
Mine (2009 Gen 2, 93K) rattles after a cold start for the first few minutes. Once things warm up, the sound fades away.
