2003 Escape XLT - Whining noise?
 

I honestly don't know where to start. This whining has been going on for maybe a month or more and I'd like to diagnose it so I don't destroy my car by ignoring it.

It seems to rise in pitch when accelerating, BUT sometimes when I take my foot off the gas, the whining remains. I don't believe it's a wheel bearing (I've experienced those on my Impala) or low oil, and it doesn't seem to be related to steering. I figure I'm left with a belt, possibly the transmission, maybe check the steering fluid, or something else in the engine I don't know about.

What is the most likely suspect and how do I get rid of the whining?

The first thing that came to my mind was when the catalytic converter in our '02 started to plug up. There was a minor loss in power, but not enough to make me think the CAT was plugging. We had a slight whine/whistle sort of noise too. Turns out it was the exhaust finding an escape (no pun intended) through the EGR valve.

Being an '03, I would check the alternator, idler, A/C compressor, ect. If the whine is only at speed and not idle (assuming you have a 4X4), I would check the intermediate bearing on the drive shaft.

It is a 4x4, yes. I do think that the whine is still present at idle, just softer.

Crucial to find out of the whine is at idle/engine rpm so engine-related or occurs with road speed and drive-line related.

If it IS present at idle then only stuff spinning at 0mph is relevant, that means engine, ancillaries and the gearbox input/torque converter.

You can use a long screwdriver as a stethoscope to fine the source and you can confirm by removing the appropriate belt (water pump or alt/pwr steering).

I know you said you don't think it is related to steering, but please double check that. The power steering systems on some Fords are notorious for making whining noises. I replaced the power steering pump and hose on my family member's Tribute and the noise is gone.

Well I know it doesn't make a difference whether I turn left, right, or go straight, but I suppose it could be the pump. I'll have a look/listen.

If you think it is your transmission, I assume it is an automatic - might look at how old the fluid is and how clean it looks. The service interval is like every 30k miles. If you replace it or not, might add some Lubegard Red or Platinum in with your ATF.
Good Luck and please share any details if you figure something out - good or bad.
ken

When you hear the whining and it's safe to do so, slip it into neutral and coast. Engine will drop to idle. Does the noise continue?
You can check for a plugging Catalytic converter by loostening the riser from the EGR valve and starting it. There should be some exhaust pressure, but not much. If there is a lot, the CAT is plugging up.