Fuel and Temp Guage during starting Engine

[Yoda]

It's minor but got curious. After I switch on the ignition key and wait till all the warning lights to go off and I start the engine like the advice post here. Sometimes the fuel and temp guage just stay at the same position but sometimes they just drop and jump back after the engine has finish starting

[Yoda]

Anyone check on this? And when the needles drop they make the vibrate too.

[punkeyfunky]

When you flip the key to start, the solenoid opens the circuit that directly connects the battery to the starter motor. The amperage required to turn the starter (and therefore engine) is huge, and as such, the rest of the circuits in the car might not get enough juice to remain opertational. Same reason why your radio (and other things) goes off when you start the car.


-Lee

[Yoda]

But it's strange that sometimes the needle just stay there but sometimes it drops.