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Since i bought the car, there has been a little noise coming from the rear after i shut the car off, i guess it's the fuel pump motor shutting off. Had fuel filter replaced about 3 months ago because i thought the car was driving sluggish and it might help out a little. There has always been a slight humming coming from the fuel filter area but after i replaced the fuel filter, it got louder while driving in stop and go traffic for over an hour. About a month and a half ago the sound while driving started to get really loud to where it was very noticeable.

About 3 weeks ago, was about 70 degrees outside, i was driving for about an hour and a half in the morning and the sound was really loud. I stopped to do what i had to do for 30 minutes and i got on the highway and headed to work. When i got on the highway sound was still loud and it felt like i was running out of gas. Car was chugging a little. I got scared and pulled to the side and it finally did stall out. I thought it just overheated or something. Wouldnt start up. I waited for an hour for the tow truck and when he got there, i tried it again, it started with a little struggle. I decided to let it sit for for the weekend and try it again. Started right up the next day. Let it sit for another day and decided to drive it to work. Just drove it on short deives for a few weeks, to and from work mostly and it was alright. Sound wasnt thrilling me but it worked.

I just moved 30 miles away from my job............First day to work, took me 25 mins to get to work, no traffic, car was alright other than the sound. Major traffic home, took about an hour and 20 minutes, stop & go most of the way. I get off my exit luckily and then it starts feeling like running out of gas. I barely made it home. Thought it was gonna stall a couple of times but got lucky and made it home. This was two weeks ago.

Yesterday, i was driving it. Drove for a few minutes and let it sit for 10 mins. Drove a few minutes and let it sit for a half hour. Drove a few mins and let it sit for 4 hours while i did some movie hopping. Drove home 15 mins and let it for 30 mins. Then i drove it on the highway for 10 minutes to drop a friend off and on my way back on the highway it was alright but when i got off the highway i got the same running out of gas symptoms and the noise was noticeable at the time. When i tried to go over 40 mph, the car wouldnt let me. rpm's wouldnt rise over 3000 adn i could only drive 45 - 50 mph for the 2- 3 minutes it took me to get home. I parked in my drive way and hit the gas a little. Still rpm's wouldnt go up over a certain point and felt a little shaky like running out of gas.

Had plenty of gas in the tank each time. Over half a tank each time. I told the mechanic the symptoms and they said it's the fuel pump without looking at the car. They said its a $700.00 plus job since they have to take the rear end off. I put some marvel mystery oil in the tank on their advice. But the third event happened after putting the marvel mystery oil in it. Maybe it made it worse because the problem seemed to happen sooner than it has been happening.

I dont know. I'm not a mechanic. I don't know what to do. I cant afford to spend 700 bucks and not have a car that runs. The car cost me my job too. I was gonna quit in 2 - 3 weeks anyway but would liked to have had another paycheck. Happy times.

 

The easiest way to determine if its a fuel pump problem is to measure the fuel pressure, at idle and under load. A fuel pressure test gauge is $35-40. It screws onto the Schrader valve, behind the passenger side head. See Shoebox photo:

http://shbox.com/1/fp_reg.jpg

You should have 41-47psi at idle, with the vacuum line off the fuel pressure regulator. Reconnect the vacuum line, and fuel pressure should drop proportional to intake manifold... about a 6-8psi drop from the "no vacuum" pressure, assuming you have a stock cam. If it passes this test, tape the pressure gauge to the windshield, and take it out on the road, running it up to max attainable RPM at wide open throttle (WOT). Pressure should never drop below 40psi. If it does, your fuel pump, or the fuel pressure regulator is deceased. If its the fuel pressure regulator, you probably would have found wet fuel in the vacuum line when you disconnected it.

If it is the fuel pump, the "book" method for replacing it involves dropping the rear axle assembly and exhaust, so you can drop the tank..... not as overwhelming as it sounds. But many people cut a small access panel in the package shelf, right rehind the rear seat, to allow replacement of the pump without dropping the tank. There are posts in this forum that contain links to illustrated writeups on using this method.

But.... test the pressure first.