2000 Kia Sephia LS having problems starting

I have a 2000 Kia Sephia LS and its been in the shop 2x trying to figure out why it won't start up. It starts up when it wants to. It has been taken to the shop and sat there for a couple of days and started right up for the mechanic, in fact, it starts up every time for him and takes 10 minutes or so for it to start up for me. They fixed the thermostat saying that the car wouldn't start cause it was thinking it was too hot. Could this be it? Or a short in the wiring / faulty ingnition switch / fuel pump?

The starter is fine.

Please advise

i think the fuel pump could be the cause, i've replaced the fuel pump and before it died completely the car would start whenever it wanted to...

JQ
www.k-rev.com

what is left of your b2b warranty. if you have 5/60 b2b on your car take it to the dealer and have them hook a fuel pressure guage up to the fitting on the fuel rail and see if it bleeds pressure as it sits for durations of time. if it does then you have an answer: fuel pump. if not you may want to look into something along the lines of the main relay. main relay failure is fairly common in lots of cars.