My 01 Elantra has just under 80K on it.

Lately I have noticed that, if the car does not run for a day or so, the engine will sound VERY bogged down when started. The engine sounds like it isn't getting fuel. There is a very sluggish glug glug sound to it, and it sounds like it is going to stall, but after a few (10 or so) seconds, it climbs to normal idle.

Stepping on the gas makes the sound worse, and the glug glug sound becomes more pronounced, however stepping on the pedal DOES make the sound go away, and after a few presses the engine sounds normal.

What is causing this, and how can I fix it? I think it's fuel-related, but I can't be sure.

 

I've had this "sluggish issue" before and it was the spark plug wires.

The wires looked fine, but apparently they were bad; however I am having this issue again but
I was also working on the power brake booster.

The engine has a vacuum thats required and if there is a leak, to where air is being sucked in it also throws the engine and it runs sluggish.

One idea I read was to lightly spray the vacuum hoses with carberator cleaner (spray), while the engine is running.
If it blogss down, you've possibly found the leak.

My vacuum leak was apparently inside the brake booster, as I stepped on the pedal the car would bog down.
This is an expensive repair or a cheap one/with alot of manual labor.

but thats another thread.

I'd try a new set of plug wires and plugs first. There's probably better ways to check it all out, but thats my suggestion.
The vacuum maybe an issue too, but I was told by a long term Hyundai reapir guy, the Check Engine lite will come on if its a vacuum leak.