2005 2.7 liter high pitch sound after starting

My 2005 2.7 liter has a high pitched whistling sound after I start it. It always has I am pretty sure that is fine. However the high pitched noise recently started sputtering instead of being a steady high pitched sound when I start it. I would like to know if it's an easy fix I can do myself or if I should take it in? I know how to do basic work on my truck like oil changes, battery swaps, rotating tires. Advice would be greatly appreciated thanks!

 

There are others on here more experienced than me, but it sounds like a pulley bearing going out, or something involving the whole belt loop..water pump,alternator,ps pump,idlers,ac compressor, etc

 

I would agree with @AJwisco. You could remove the serpentine belt and start the engine. If the noise is not there any more then the problem is with one of the components driven by the belt. Don't run the engine very long. Just long enough to determine whether or not the noise is still there. Remember, the water pump is driven by the belt.

 

Video of said sound?

 

Since you are there, you might want to check your PCV valve and see if the line from the PCV valve to the throttle body is still open. Since the PCV valves are made of plastic, it should be changed every 30K. Sometimes people in hot climates [like me] make the mistake of putting half a quart extra of 10-30W oil in the crankcase and never changing the PCV valve until 100k miles. Mine was clogged in the closed position and this leads to leaks out of the valve cover. Like a dumbass I've been putting in fuel additives like Lucas to stop the leak for 5 years.

I then had that plastic coolant bypass pipe break on me one winter. So since I was already down there installing one of those new metal coolant bypass pipes, I figure we should redo the valve cover and intake manifold gaskets too. That's when I noticed the PCV valve was stuck in the closed position. It was the blocked plastic PCV valve that was causing all the leaks when I run it over 3k rpm.

After new gaskets and a PCV valve, it stopped leaking. There was a reason Toyota Engineers kept the torque low on the valve cover bolts. If the pcv valve failed, the extra pressure would be released through the valve cover gaskets and not in the more important parts of the engine like the main seal. Then the oil would collect in that passenger side corner of the engine and drip behind the heat shield and burn off on the exhaust manifolds. Those Toyota engineers were smart. I always wondered why they decided to tilt that 4 banger that way.

Anyway, yours might one day throw a code. Mine was throwing a P0420, catalyst efficiency below spec. After vacuuming acetone through the upstream oxygen sensor port and back into the tailpipe, I was able to clear the code and do a drive cycle to make the monitors say ready. Going through the PIDs, I noticed the A/F was running very rich, double digits rich. I chased the cause to a cracked PCV hose letting unmetered air into the system. So what happened was that the ECU was thinking there was too much oxygen and was dumping extra fuel and opening the EGR valve from exhaust to the intake making the exhaust extra dirty and this extra carbon would clog the cats over time.

I just double checked my engine for that high pitch hum sound you had. Yep it's the PCV valve and that's normal. If you don't hear it then it's probably clogged or the hose leaving from it to the throttle body is clogged.