Problem With Fuel Pump?

[jfk1232]

My 1990 Laser has a problem I've mentioned before. When low on gas, it will die when being started or idling and will have black smoke come out the tail pipe. It will also have problems accelerating where it will not accelerate and start jerking. If gas is put in the car, the problems go away.

Someone told me that the problem sounds like the fuel pump. If it isn't installed correctly, it can have problems picking up gas sloshing around when the tank is low. He also said it would explain the black smoke coming from the tail pipe. Does any of this sound right?

Someone else, by the way, mentioned it might be the computer. I don't know if the computer would cause problems only when low on gas, however.

[rubix777]

Maybe when you are low on gas, the car is using the crud at the bottom of your gas tank.

[curtis73]

Black smoke is always too much gas. It almost has to be a bad sensor, a leaking injector, a stuck fuel pressure regulator, or something up front. You may have a problem with the pump which would explain why you have trouble when the tank is low, but the black smoke is too much fuel... period.

[mazdatech177]

hey buddy... would you pull the tank out and look for crud or water in the tank please. that is where your problem is..... period. sensors dont just decide to go bad when you get low on gas. black smoke is incomplete combustion, which in most cases is from too much gas. but it can also be from incorrect spay pattern of the fuel injector resulting in improper fuel atomization. if you start dropping fuel pressure or volume to the injector you will get incorrect spray pattern. any sort of misfire will dump all that unburned oxygen from the combustion chamber into the exhaust stream. the o2 sensor will pick it up as running lean and the computer will richen the fuel mixture to compensate... complicating the matter greatly. that could be where your black smoke is coming from... fix your low fuel problem and go from there... im willing to bet you dont have any black smoke