I just replaced the fuel pum because I thougth tha the older fuel pump was bad but I replaced and the car keep doing the same thing after a while the fuel pressure goes down I don´t know if is because of the oil pressure sender unit isn´t working right .:confused: where is located the fuel pump relay on a honda accord 1993 or some body has a repair maunal or a electric diagram,

If it runs fine with fuel cap loose, Maybe the vent is clogged.