Hyundai Repair: 2005 Elantra fuel gage, fuel level sensor, fuel sender

Question
I'm having the same gage trouble as Jessica on my 2005 Elantra with 35,000 mi, bought used a month ago.  Gage suddenly jumps down and gas light comes on.  My son only had $3 with him, put that in and gage jumped to 1/4 full and he said huh? well unless the tank only holds 4 gallons. :-) My mechanic says fuel level sensor also but likely needs to replace the whole fuel pump assembly @ $650 does that sound right?

Answer
Most likely, the fuel sender is indeed the issue, but even though it is a part of the fuel pump assembly, it can also be purchased and replaced separately.  If the mechanic hasn't already done so, have him check the parts department at the local dealer.  If they don't have the sender in stock, they can order it.  I'd expect the price of the sender to be around $100 or less.