2000 HX manual transmission with 310,000 on the odometer.

Every once in a while I notice what can best be described as a "rumbling" coming from the front end that goes away completely when I let off on the accelerator. The rumbling can be heard as well as felt. I was thinking it might be wheel bearings or axle u-joint but the only time it happens is when it about to rain, raining, or has recently rained.....i.e. - high humidity.

Now I'm starting to think catalytic converter, an injector, or maybe even an oxygen sensor. Everything under the hood is still original except for obvious things (plugs, air cleaner, etc.) and the EGR valve which was replaced a couple of months ago because the old one failed.

 

Also, it's not speed dependent.....it happens in all gears.

 

Sorry I can't help but damn that's a lot of miles.

 

Actually, it's not really that many once the type of driving is taken into consideration. Mobil 1 oil and filter changes every 5000 miles.....I have an 80-mile commute, the car gets started only twice a day and spends 95%+ of its time on the interstate. The cylinder walls still have hone marks. Original clutch, too.