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Hello everyone! I'm trying to find if this sound it's the oil pump. It's a very audible whining sound that comes from the engine, TB side. It started last year when I did an oil pan replacement accompanied with the oil and filter change too. I bought a Z6 oil pan (someone already confirmed that its the same part number) It literally started when I turned the engine on, before that it didn't do it. Previous owner didn't told me what viscosity of oil was in there, I put a 10w40 as by chart it matches the temperatures of my region (I could use 5w30 too but it seemed too thin for a engine with 330k km) since that first start up the oil light remains on at cold starts for about 3seconds, while the whining persist more that that (I usually use the cars only on weekends) an it disappears when engine it's like 3 to 5 minutes on. Those two symptoms make me worry about the oil being too thick, the oil pump going out( out of knowhere? And without any other apparen reason) or the PS pump in the best case, it's like 90% discarded because even with top off liquid it still does the sound, and sound doesn goes up or down when turning the steering wheel, although I got a leak from a hose because it only leaks when parked. I'm near the next oil change by time not mileage. I'm planning on change the oil grade to see if the problem disappear or gets worse, I already put some anti friction additive to prevent any sort of damage that those 3 secs of apparently oil starvation could do.
To further diagnose I'm going to run an oil gauge into the dash to know if I things get worse. And take out all the acc belts again just in case.
Oil light doesn't comes up never while driving, not even while idling, or at highway speeds, also I don't abuse the car to give any apparent reason to the oil pump to go out from one moment to another (that's why I'm asking)
Thanks in advance and sorry for the long text