Idle drops, rough shifting, MPG hit
 

Hi guys.
I recently moved my 97 Del Sol Si (Automatic) from Texas to New York.
Now that it is no longer the dreadful winter, I've noticed some small nags that my car hadn't had before.

First issue is after driving long enough to warm up, the car will have a somewhat rough idle. Where the trouble really starts is if I give it a rev in park. The engine revs up, then drops to below 500RPM, almost stalling, and then evens back out to about 700RPM.

While driving the car will have pretty hard upshifts when accelerating. I'll take off normally (as in not like a douche) from a stoplight and the car will rev up, and then when it shifts the the second gear ratio, it will lurch a bit and have a rough shift. It does this to a lesser degree up to the 3rd and not at all once going up to highway speeds.

I've also noticed a measurable MPG hit. Used to go 360ish miles on a tank on highway and 280-300 in city, but those have come down about 40 and 30 respectively.

Could this be water in the gas? I have not had this issue until I moved up here. I don't think this car has ever seen cold weather (Florida-Texas its whole life) and it ran just fine when it was cold out.
This started a few weeks ago now that it is finally springtime.
I was thinking about checking the engine for gunk, since there is a buildup of that de-icing crap that's all over the roads.

Any thoughts would be appreciated, thank you

Re: Idle drops, rough shifting, MPG hit
 

Was also wondering if this could be the symptom of crappy gas?

I haven't run any diagnostics at yet, I'm trying to get some info while I'm at work before I go do anything to it.

Re: Idle drops, rough shifting, MPG hit
 

took a quick look at lunch.
I thought it could be vacuum, heard this whirring sound.
upon closer inspection it is the water pump that is whirring.
The weird thing is, now when in park it doesn't bog down, but it does when I come to a stop while driving.
At this point I can't think of anything specific and I really don't want to put more money into this since I'm getting a new car next month