RonH

It may not be the issue in this case, but pumps do indeed go slowly out. It is not unusual for a pump to run fine for a time, and then the vehicle will just die while running down the highway or sitting at a stoplight. Then the vehicle will start right back up and run for another seemingly random period of time. Pumps do not always just fail completely all at once.

jmack91z28

Your probably right but i've never heard of that. Just wandering, how can an electrical pump slowly go out? A circuit can either be open or closed, how does it slowly open? I have heard of the fuel pump relay going bad and it chatters causing the pump to start stop, pump never the actual pump slowly going bad.

RonH

In order to deliver the proper volume of fuel and maintain pressure to the system, the motor must turn at a certain constant speed. For various reasons such as worn or damaged bearings or other components of the motor, the motor mightnot always turn at therequired speed. Running the pump dry by driving the vehicle to an empty tank can damage the pump. Also running it with a low fuel level in the tank can cause the pump to be damaged by overheatingbecause the pump needs to be submerged to keep it cool. The pump impeller might be damaged, or there might be some foreign matter in the pump restricting the flow. Some component of the pump unit may have just beendefective when it was manufactured and it is finally failing. There are any number of reasons and, as I said, it is not uncommon.

jmack91z28

Ohh ok, well that makes perfect sense, didn't think of it that way.

Houston36

i wouldnt say that its got progressively worst but the idling problem started happening off and on probably 6 or 7 months ago. Then in the last two months i noticed it didnt have as much power sometimes. Then on the way to school one night it started bogging down while accelerating then died when i got in the parking lot and took me 30 minutes to get it started when i got back and its been doing it off and on since then but now its every time i crank it up.

about what RonH was saying about the fuel pump, since when i very slowly give it gas the engine accelerates just fine could this still mean the pump could be at fault?

RonH

How much gas is in the tank? It takes more effort for the pump to lift the fuel when the level is low, so you can have a good running vehicle when the tank is full, but it won't start or accellerate on a near-empty tank.

Houston36

probably around a quarter tank cant say for sure cause the gauge doesnt work just goin by the miles

Houston36

did a fuel pressure check today and with key on and engine off it was around 40 psi, while idling it was between 35 to 45 and when i turned it off the pressure dropped probably 10 psi in a couple minutes

jmack91z28

Well that about proves it's not the pump if it's got pressure, and thats about the correct pressure too i'd say. Just so I can shut up and stop worring about it have you checked the injectors and the resistance across your sensors?

Houston36

finally got it fixed, drove it around until started acting up and checked the pressure again and it wouldnt get above 20psi so put a new fuel pump in today and she runs like a champ and thanks everybody for the help