Fuel Pump?

malibu
chevrolet

#1

I have a 2000 Chevy Malibu 3.1 engine with 130,000 miles. I recently made a 500 mile one way trip with no problem, on the way home, I had traveled about an hour (70 miles) when the car just died. I pulled over and it started right up. I went another 10 miles or so before it quit again. This kept happening until I could only go 1/2 mile at a time. I spent the night in a hotel, and the next day, the same thing happened. Go for an hour, no problem, then the same thing. The dealer mentioned fuel pump. Does anyone have any thoughts? Why would the fuel pump run ok for 1 hour and then keep shutting off? At the same intervals one day after the other?


#2

If the fuel pump is overheating it could cause that behavior. It runs until it gets hot, then shuts down until it cools off some. Some fuel pumps are in the gas tank and are cooled by the gas, so this happens more when the gas level is low and less when the tank is full. Some fuel pumps are outside the tank, though. Not sure about yours.

There might be other problems but it’s a logical first guess. The only way to be sure would be to put a pressure gauge on the fuel line. Drive the car until it dies, then have someone crank the engine while you check the gauge.

I assume it would crank well but would not catch. If it doesn’t crank then something else is wrong.


#3

No one is going to get anywhere just guessing. A fuel pressure gauge will tell you whether the pump is a plausible explanation. There are reasons that it would work for a while and die - most of them having to do with it getting all heated up as it works.

But someone is going to have to actually lay their hands on the car. There isn’t just one possibility.

You don’t need to use a dealer. Any good independent mechanic can check things out.


#4

The fuel pump is in the tank, I kept the tank full. It never got below 5/8 tank. Yes, it would crank well, and the tach would move, which would rule out the cam sensor???


#5

Finally got the car home today. Still cutting out every mile or so. Checked the fuel pressure and it is good. What else could it be besides the camshaft sensor???