ok so i have a 91 civic hb std with a ls motor i just put in, i am running obd 0 with a pr4 ecu and my car is in limp mode with a code 4! what is a code 4 and could it be because i dont have the o2 sensor in? lemme know thanks!

 

From google code 4 is the crank position sensor. Oxygen is code 1.

 

is it a zcls motor? They dont have o2

 

they have o and o3, but no o2

 

its a b18a1

 

zc