Fuel pump issue?

Can I assume the car is driven very little? If it sits for long periods, there may be mold growing in the tank. It feeds on the alcohol in today's gas. That mold can cause two problems. One is it plugs the pickup screen on the bottom of the fuel pump housing. Depending on the design of the fuel delivery system, that can cause the engine to sputter or stall when the highest volume of fuel is being pumped, which is during coasting. The engine typically runs better at highway speeds and when accelerating.

The second problem is that mold, along with other debris, can clog the pump's impeller. That can cause the pump to run slow or fail to start up.

One frustrating complaint that we used to hear all the time was the owner replaced the pump up to a half dozen times with aftermarket replacements, then, out of frustration, bought one from the dealer, then had no more problems. In fact, there was nothing wrong with the aftermarket pumps; some even come from the same suppliers that made them for the car manufacturer, but by the time the dealer's pump was installed, all the debris had been collected and discarded with the previous pumps.

There have been service bulletins related to this problem. The recommended solution was to take the gas tank to a radiator repair shop to have it steam cleaned, then install the new pump.

The debris I referred to is microscopic. It isn't anything you can see.

The next step is to do an autopsy on the pump you're removing, but that will likely void any warranty. You can start with the bench-test by connecting a battery to see if it runs. Be aware the brushes in the motor cause arcing which can ignite gas fumes. It's much too rich inside the tank for that to happen. An alternative to start with is to measure the continuity of the motor. If you find an open circuit, there could be debris that got stuck under one of those brushes. That might prevent the motor from starting up, but if it does get up and running, it should continue running until you stop the engine.

If you do connect a battery and you see a little sparking when you make the last connection, it proves current is flowing through the motor. It should be running unless the impeller is locked up.

If this current pump has never worked even once, given your other observation of the gas gauge not working, it would not be too farfetched to find the assembly is wired wrong. As a former manufacturer's instructor used to tell us, "we not only sell you parts; we sell them to you pre-broken". The wires are hand assembled into the connector. It's easy to see how a mistake could be made.

Since this pump did run for a few minutes, you might look in a different direction at what these have all had in common. Mainly I'm thinking of removing the tank and unplugging the connector. Look for a corroded ground wire that is making intermittent connection, and even better, check for intermittent connections in the connector terminals. I used to warn my students to never poke test probes into the connectors for fear of spreading them, leading to poor contact with their mating terminals. If the pump passes the bench-test, use small pick to squeeze the connector terminals tighter.

Another thing to look at is how the pump motor is grounded. GM used to have a really common problem with their motors being grounded right to the tank, then the connection back to the battery was made through the two metal straps holding the tank in. Those straps were notorious for bad connections. The fix for them was to drill a small hole through the flange where the top and bottom halves were welded together, outside that weld bead, then use a self-tapping screw or a small nut and bolt to attach a ground wire from the tank to the frame.

Let me know what you find with the bench-test.

"Put it all back up nothing". What does, "nothing" mean? The pump was not running or there was no problem?

Twice in 440,000 miles, the pickup screen became plugged on my '88 Grand Caravan. Just a $12.00 part, but both times, when I reconnected the two hoses, I switched them, even though they're different sizes. I'm supposed to be the expert! The pump was trying to push fuel into the return side of the pressure regulator instead of to the injectors. Luckily it was just a three-minute job to switch them to where they belonged, but it shows we should never assume we did everything correctly. I did that TWICE!

It sounds like you have this solved. Let me know if it acts up again.

Dandy. Please come back to see us with your next dilemma.