Engine has 30k+ miles on it. It gets about 23-26 mpg, manual transmission.

Whether cold or warm, stationary or moving- engine makes odd sound which increases with rpms. It sounds a bit like galloping, it's kind of deep- not whiny, not screechy, not pingy, not clicky/clacky- more like a sloshy pumping sound. I think there's a faint hissing sound too. This sound is 0-3 miles old. So far there is not change in performance. There is a belt that looks like it goes between an air compressor? and power steering pump? that wobbles a bit but seems to have proper tension. it has no other issues, everything else functions at 100%, and really drives like a dream.

anyone want to take a guess at the source of this noise?

 

The manual 4-cyl's are prone to steering pump failure.

 

solved!

The power steering pump pulley had some belt teeth wedged firmlyin its groove. The pulleys belt path then became oblong, the belt began to slip, and as a result the varying tension began to throw everything off and make a horrible noise. The belt was replaced.

Not long after that some thieves stole the battery out of my other car and any easy, non-alarmed car in a 5 mile radius. frickin tweakers! So I bought a cheap car alarm that hooks up right to the battery. I should check the ground on it.

I now have a new problem. The idiot lights start up and run a regular check. Everything seems fine, none of them stay on. But the battery seems to be weaker every day. This morning it tried to turn over but couldn't. Icompression started it and the alternator ran the car. After awhile the battery was charged a little more.

We have been having very cold (and warm) weather here. Maybe the battery has an excessive drain on it? (car alarm?)