so i'm installing new guages in the dash, i have the fuel gauge all hooked up it works fine, drops to E when car is off and goes to fuel level when on. while driving, when i hit the gas the needle will drop to E then go back while driving. also it will drop when turning. where do i look first? fuel sender unit? or anything easier i can rule out first?

 

Fill the tank with gas and then see if it still does it.

 

sounds like your tank is low on fuel... Is it? if not i would look for an electrical issue just to rule it out. it probably will be the sender unit, but ruling out an electrical issue is cheap, and in the long run can save you a ton of $. replacing the sender unit and then finding out it was an electrical issue, can be very costly.

 

i have about a 1/4 tank left, ill have to fill it and check it out

 

That's absolutely normal when you get down around 1/2 tank or less. Lower the level the more it changes when you corner or accelerate.