Hyundai Repair: 2000 elantra erratic rpm, throttle position sensor, maf sensor

Question
My problem:
At idle or while coasting to a stop(basically anytime my foot is not on the gas), the rpm will drop quickly and I feel a loss of power.  Most of the time the rpm recovers by itself.  Sometimes if I give it a little gas that will help.  But sometimes no matter what I do the engine stalls.
The Check Engine light usually comes on, but the computer shows no error codes.  Please help.  Thanks.

Also:
1) The problem goes away during the cooler months.
2) Even during the summer months the problem does not occur every day.  But there are some days when the car seems bound and determined to stall.


Answer
Hello Roger,
You might have a bad maf sensor or throttle position sensor. It is really hard to tell without the trouble code. If your check engine light is on than there should be trouble code/s stored. Did you try to scan with a professional scanner? Because , some codes are factory specific codes and regular scanners can not see them.