He put it in D or R and it still in Neutral, raving the engine doesn't help. After several tries, and usually like ~5 minute warmup if finally gets in D and then the car drives perfectly fine. It only happens when cold. Any ideas, anybody already run into the same problem?? any advices appreciated. thanks

I had the same problem with my Hyundai several years ago. I got in and started the car okay but when I put it in 1st it backed up.I stopped quick because I was in a parking lot at the time. I tried to get it to change to a higher gear but it would not go in . I finally had to put a rebuilt tranny and a new clutch in it . The car was at this time 5 years old and I never had a problem with it so to invest parts in it was a no brainer. Do it and get another 5 out of it. If it is under mfg warrenty then get them to do it.

May be ab bad starter solenoid, or corroded/loose connection at starter, or (ground). Could also be a bad ignition switch. Start from the load; the starter. Test for 12V at starter, OK. Connect short wire from starter and touch sylenoid connection..

Does your vehicle have a serpentine belt ( flat and wide, ribbed on the inside)? if so,first I would check the belt tensioner. You'll need a tensioner tool ( rentable from Autozone with a refundable deposit). Before starting, observe the routing of the belt, as this is crucial to your motor ! Release the tension on the belt and slide off of the tensioner. Holding the belt out of the way, spin the tensioner. listening for the popping or snapping sound. If the tensioner is ok, check the idler pulley the same way - I'm pretty sure it will be one of the two. Other than this, I would need more specifics of your vehicle in order to research. If the motor is not running hot, I would not suspect the water pump - which may or may not be operated by the serpentine belt.I would not run the motor until you determine the problem - most newer motors are interference motors, meaning the pistons cannot be in the up position while the valves are open, or else serious damage will occur to the valves ( typically the exhaust valves and guides are severely damaged).Also, if it is the tensioner or idle pulley, you could lose the belt while driving which would knock out your power steering, alternator, and possibly your water pump.
I hope this helps and thanks for using Fixya!!

IDLE Sentsor

Sounds like maybe a motor mount may have broken,if you
open the hood and put the car in drive ,then neutral then reverse
the engine should only "rock" about an inch or so,if it really jumps
that is the problem.

Do an upper intake clean that will clean the throttle body and the Idle Air Control valve. Also clean the mass air flow sensor

it sounds like you are floding the carbureter with fuel

2 things, first have the battery checked/replaced. if all is well with battery. second, very unlikely, its the switch that makes sure you are in park or neutral before engine will get contact.

hello,for this problem sop to install a fuel gauge,to determine your fuel pump motor is working(fuel pressure) or fuel filter is not clog,we have a report a case which diaphragm pressure regulator is leaking this is only in fuel side,try to start your engine,remove 1 spare plug to determine that you have a ignition,if not send to your dealer,ty

Neutral safety switch allows you to start thr engine in neutral or park only