Have a problem... My truck is making a strange weeering sound that changes in pitch as the engine idles. This started happening when the weather got cold and was intermittent when engine would be cold and would completely go away once things warmed up. But now its getting louder and more consistent. Its loudest when first started up when cold and gets higher in pitch and louder when engine RPMs increase. As things warm up it gets quieter but you can still notice it at idle and gets louder when RPMs increase, but not as loud if the engine was cold. This all started when the weather got cold and like i said was intermittent, but now its almost always there when i start the truck up in the morning or after work. I popped the hood tonight when i got home from work and its sounds like its coming from the front of the engine (pullys, belts). My guess is a pulley bearing somewhere, but everything is so noisy i cant pinpoint it. If it is a bearing, iv never heard a bearing go out like this, im use to a high pitch sequel. Im hoping its only one of the belt tensioner pulleys and not a water pump, power steering or alternator.
Hoping you guys can shead some light hear on what it might be and how to pinpoint it. Also why does it seem to quiet down when the engine temp goes up?