How do i know if my ECU is throwing any codes?

[leesredgt]

Ive went through everything on my car thats should be causeing it to hesitate but its still not fixed.Its either a bad gas tank or a bad ECU.So my question is how do i know if its throwing any codes.Theres no light on my ecu or if there is it dosent light up.The car feels like it has a bad MAF it wants to hesitate around 3-4k rpm.Ive went through every thing and these 2 thing are all that i can think of. Thanks.

[leesredgt]

anybody?

[nissans13240sx]

Should be a knob on the side of the ecu, you need to turn it. A red led will flash, count how many times it flashes and look up what that code is. I believe key must be on to do this.

[leesredgt]

thanks u sooo much, i really appreciate it.