Replaced the Fuel Pump & Vacuum Lines

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Copied from another page, which is why it reads weird.

Took about an hour and a half, but it's done. The new fuel pump installation wasn't as difficult as I thought it would be. I didn't have to drain the tank and lost very little fuel in the process.

The new pump ran nearly $215. No one sold it cheaper than ~$180 so I stuck with my loyal parts haven Pelican Parts. Shipping is decent and they have virtually anything you might need for a 944. The new pump is blue, the old green as I found out. The new pump came with a preinstalled check valve, which are notorious for failing on these cars.

Removing the pump is done quite easily. The pump hangs beneath the tank and is totally independent of the tank itself, attached only by a metal strap and a few wires. Disconnect the battery whenever working with fuel. Remove fuse #34 and attempt to start the car. Without the fuse in, the pump is disabled. Any gasoline in the fuel rail might combust but ultimately you're looking for a stall. As it should, it failed, and purged most of the gasoline from the fuel lines.

Jack the car up from the rear and remove the metal strap which holds the pump cover on. It's pretty straight forward from there. Before removing the line from the tank, clamp it off with a pair of locking pliers. Be careful not to rupture the hose or pinch it off. Basically, all that's needed is enough force so that it doesn't leak out. Remove that hose from the pump, the banjo bolt from the check valve, and the wires and pull that baby out.

With it out, it might not be obvious how to remove the rubber case from the pump. It's a giant sleeve, fitting tighter than Oprah in a Mini Cooper. Eventually it'll come off. I used screwdrivers to work the rubber from around the top, carefully, and it came free. Putting the new one in is just as much fun.

I believe the following picture shows where the leak originated. One of the copper crush washers must have failed and gas leaked from around the banjo bolt. I bought two new copper washers at fifty cents each for the new pump. These are *not* included in the Pelican Parts pump though. Clean up the area and installation if the reverse of removal.

Removed the hose clamp, reinstalled the pump fuse and the battery, and used my DME jumper (a wire that turns on the pump without the need for the car to be on to flush the system with pressure and to test for leaks. Everything looked good. Solid pressure, no leaks at either the clamped hose or the banjo bolt or up at the fuel rail (since I just replaced the fuel pressure regulator). For information about creating a DME bypass, go here.

Took the car for a spin to get the pressure built up and going and all was well. Have a ticking fuel injector which will be inspected soon enough when they're cleaned and painted. Idle was smooth, pickup was solid, and no sign of anything foul. However, without actually driving the car on a good 10-15 mile trip, the length of time it would take to fail the prior setup into stalling, I cannot be sure it's a fixed scenario. When warm, inclines would cause stalling, with no amount of throttle stopping it from happening. I figured fuel pressure, but I'm still investigating it.

Also, replaced the vacuum lines on the car, including the fuel pressure regulator.

[zedsn]

Hi, why you had the pump off unless the fuel filter was newish then would have been a good time to replace that as well.

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The filter is new, yes, having been changed only 1000 miles ago.