I have a 2003 N16 Nissan Pulsar sedan, 1.8L vehicle. Sometimes, when I insert my car keys into the ignition, and switch the car on, it doesnt start, and the car is making noises (trying to "rev"), but the car does not start. I then take the key out and try to start it a few times without success. However, I do notice, when I turn the key once to the first click, it makes a "click" noise, and then the car actually starts up normally. This is not the first time it has happened, and it seems to do it irregularly. Can anyone tell me what is wrong with my car? is there something wrong with my key, my ignition, the fuel pump system? Help! Kelly

Hi Kelly,
sounds like your battery is a bit sick. Or it could be the starter motor solenoid sticking.
The click you are hearing is probably the starter motor solenoid. If you hear a series of loud clicking its usually due to a flat battery in which case you need a jump start from another car.
If you can get someone to charge up your battery using a portable charger and the car starts OK, its a fair bet your battery is on it's way out. You can get your battery tested at any large reputable auto repair shop.
If the battery is OK, the solenoid can get stuck on your starter motor. Often a light tap with a rubber or wooden mallet can free up a stuck solenoid, but ultimately you will need a new starter motor. (BTW The solenoid is the smaller bit attached to your starter motor. There will be heavy wires attached to it) Have a look at link 1 below for more info.

Have a look here for some info to help you understand your starter circuit:
http://www.samarins.com/glossary/starter.html
or
http://www.caradvice.com.au/37/car-doesnt-start-engine-doesnt-start/
or
http://www.ehow.co.uk/video_5225934_diagnose-bad-starter-motor.html

Regards, Steve
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