1999 C230 Kompressor, engine fuel/shifting problems.

I bought a used 1999 C230 Kompressor about 15 months ago, and bought the old line of "The wife just uses it for her long distance commute..." hook line and sinker. I'd found that outside the mandated service checks to maintain the warranty, the previous owner took very poor care of it.

Maintenance I've done (or had done):
I've had all the belts changed, had the brake system (but not the master cylinder) replaced, had the fuel filter changed out. Regular oil changes with full synthetic at the dealerships suggestion (but done by my own mechanic.) And changed the air filter about 600 miles ago.

So after the initial rough spots of taking over from the previous owner, getting things cleaned up/out etc... The car has run like a dream. Until yesterday afternoon.

In the morning it ran fine. No problems that I could recognize (not that this is a good indicator though)

I come home, car sits in the drive way for about 2 hours, and I hop in to run an errand, and the car at first feels sluggish.

By sluggish I mean that when I push the gas pedal, instead of getting the usual forward response, I get a pause, and more of a creep forward than the usual lurch. about 4 seconds later, it starts to pull forward.

It gets to about 30-35 miles an hour, and feels like it wants to shift to second, but does not. Even with the proverbial pedal to the metal I get little to no response.

First thought was "oh #[email protected]%!, my transmission is going out."

Took the car to a nice straight-away.

Dropped auto-transmission into 1st, accelerated, shifted to 2nd smoothly, accelerated more, and into 3rd. But still hesitation on shifting, or no shifting at all from 2nd to 3rd. Max speed was around 40mph.

Figured it wasn't the transmission.

Took it home and popped the hood. Put it in "park" and listened to the engine. I pulled on the accelerator linkage, and the engine seems to rev up and then probably around 1500-1800 rpm (scientific wild assed guess) I'd hear a pop sound. But not a popcorn pop sound. more like a pressure releasing from a soda bottle kind of sound. (But I don't know if that's air, or fuel. Or too much fuel or two little or a normal sound masking as something mysterious because the car is running oddly.)

Engine seems to rev past it, and then lose power. It starts to rev up again and then lose power.

Any idea what could be causing this, and how to fix it?

Grateful for any help.
Its my only transportation, and I have a 30 mile commute on monday!
Thanks.

MadManuel

Update:

Engine seems to run in a similar fashion to other board members who have had problems solved by replacing the "mass air flow sensor"

Since my engine is now kicking off a "check engine" light, What kind of Engine code should I be looking for? Especially since a masss air flow sensor is kind of an expensive part to buy just to see if it works?

Other thought:

Thursday night, before this happened, I'd started driving home from the office, and during the drive, the fuel light came on, and rather than filling up that night, (it was a helluva day) I let it sit in the drive way with very little fuel.

Next morning, I drove straight to the gas station and filled it up.

Point of the story:
My Dad used to say that occasionally, if you have too little gas in the tank, you can get 'silt' in the bottom of the tank sucked up into the fuel system and clog carburators, and fuel injectors.

Is this true?

Could this be an issue

I'm taking it over to autozone right now, to borrow their loaner OBD code reader.