Reply from a Hyundai TechnicianI need some help as I have exhausted all my mechanical knowledge on this car with GDI motor...
Just another gasoline 4 cylinder,, no voodoo really
Things I've checked:
-I can hear the fuel pump turn on (and no issues while driving suggest its working properly)
-Cleaned throttle body (made no difference)
-Pulled spark plugs and they look good.
-Disconnected and reconnected every plug connector I could reach
-Battery and connections solid, reads 12 volts on meter.
-Car has no MAF sensor so that cant be it.
What else should I look for before throwing money at expensive parts?
Scan for DTC , best for HYundai dealer to do complete FAULT CODE SEARCH of all onboard modules and print
What makes this strange is this just began happening, but once it starts it runs perfectly. I first thought fuel pump, but wouldn't that show signs while driving too?
Has a primary low pressure pump that feeds the high pressure GDI pump.. fuel pressure test the primary pump ??
Crankshaft position sensor- but RPMs raise when turning over
Nope, starts and runs, so PCM knows crank is in motion and where
Timing belt- but it wouldn't run perfect once started, right?
THETA has a chain...
Purge valve- usually to blame after fueling, but this does it randomly after car is turned off at any time.
Expect to see a 0441 DTC if purge at fault
I'm so lost..
I'm a decent DIY mechanic so throw any knowledge you have at me, I'll be able to troubleshoot it at least!