Nothing comes on at startup...whats wrong???

[boogerdawg]

okay so my car sometimes wont start, sometimes will start. Sometimes it needs jumped to start, and sometimes it dies while im driving it. When my 240 finally does start nothing comes on at idle. the instrument panel, dome light, and heater/ac all do absolutely nothing. But then when i give it some gas and get the revs up, everything comes on and stays on even while the car is idling. What could this be? Its like i start the engine then have to rev it up a bit to get everything else to kick on, but once they are on, they stay on. What could cause problems like these????

[driftingmy240sx]

check you grounds for an excessive voltage drop. place a meter lead (red one) on a body ground and the other lead on the battery while measuring dc volts with the key on. if the reading is over a few tenths of a volt you need to fix or make some new grounds. also check the engine grouns the same way.

[boriquaS13]

Also check and make sure your ignition switch is good. Try wiggling the ignition key while the engine is running and see if it stalls or lights in dash turn etc.