Engine/Transmission (1998.5 - 2002) After you've replaced the PUMP,theFILTER

[Huff N Puff]

If after you've replaced the pump the filter and lines and your pressures are still low. Your next check is to make sure another gauge concures. After that you need to make sure your schrader valves in the test ports are not restricting your gauge readings. If the readings are still low, you then need to test pump electrical. This seems to be an overlooked point,in alot of the testing. Low voltage or weak connections can cause low pressure. A voltage drop test should be done from Positive Battery to supply line into the pump. A drop of over a volt is a problem. You then need to test the drop from the negative terminal of the pump,to negative of the battery,more than 100mv indicates high resistance on the ground. If alls good here you then need to hook up a known good pump up to the supply line from the tank and pull fuel thru the sock in the tank to check the flow of the supply lines let it pump unrestricted into a pan, if its frothy and aerated,you either have an air leak in the suction line or a restriction in the tank. Note some of these test should be done before you throw a pump at it.