Starts sometimes then dont other times - 2003 Hyundai Tiburon

It is the kill switch, ever since they but these on used cars they been acting up.

could be crankshaft sensor.

I've had this problem and it drove me crazy because I had just brought the car and it went ok for the drive home and then I went to start it again and it took ages to get it started. ( hated driving it).. I changed the oil and filter and it started first time every time.. But now have a new problem.. If I knew the problems these cars had I would never have brought one.. It makes a pretty lawn ornament though...

it sounds like the problem is the pump itself.you will probably have to have the pump replaced to correct the problem.this is how a bad pump acts when its worn out and needs replacing.replace the fuel filter at the same time

Year? model? sometimes if you turn key on, (dont start the car) then depress the gas pedal 3 times to the floor. then turn key off for 30 seconds, then start car, it should reset, but I dont know what you are working on?

I would check the fuel pressure and check the fuel filter.

replace the starter motor

Here is a great write-up on the subject. This will get rid of the entire VATS system. It was the only thing that saved my 94 Park Avenue: http://newrockies.com/vatsbypass

My 99 cougar sometimes dont start but it dont even make a noise. it has something to do with the security system. i turn on the head lights a couple of times and it will start.

check the wire connections for propper connection sounds like they aren't making it all the way