gas pedal vibrates between 900-1300 rpm/heater core drain pipe

[3100]

did anyone experience similar problem, gas pedal vibrates when pressed slowly only between 900-1300 rpm it happens during driving or when in park. Can this be ignition related like wet or dirty spark plug?

Also I recently changed my heater core and completely forgot about the drain pipe that attaches from the outside to the plastic cover drain tube that goes under the heater core. After the job was done I found some plastic tube but decided to throw it into the garbage (thinking it was part of the old heater core's plastic lines) will I really need that tube or the plastic drain tube that is attached to the plastic cover that goes under the heater core will be long enough to take ac water out or will it leak inside under the sound isolation and carpeting?

[xeroinfinity]

I wouldnt think your ignition system would hav anything to do with vibration in the pedal. more likly just engine vibrations transfering.

Yes that hose is kinda important to keep water out of the cabin. Not only from condisation but when it rains if water get in there it will drain on the floor eventualy and can also cause your blower motor to get rusty and fail.