This has been an on going thing. After about half an hour of driving the sound of my engine changes. It sounds almost like a giant fan and loses the ‘throaty’ sound. If I get back up to speed it usually goes away by 30 mph or so and the engine sounds returns to normal. There no squealing or ticking or dentist drill sounds. I guess the closest thing could be a window A/C unit. I suspect it has something to do with the temperature of the engine. The engine seems to run at a normal temperature and performance doesn’t really change at all. i just did an oil change and it didn’t make any difference. The temperature doesn’t jump up if I stop either.
The next repair which I plan to do later this month is the secondary air injector pump. I would love to have that fix this issue too but I doubt it. I’m still on the fence on if I want to keep it or not but I might as well keep it alive while I have it.
I just passed 177k miles. You want to make tow truck jokes please go somewhere else. I’m going to go DRIVE home now. Thanks.