2002 Chevrolet Blazer Stumbling and Dying - Fuel Pump Replacement

This '02 Blazer was stumbling and dying - it was restarting and running intermittently. 

This post describes the diagnostics used and the steps for this in-tank fuel pump replacement.

With no trouble code and intermittent stumbling, loss of power, and dying, a fuel delivery problem seemed likely. 

When the engine was running, the gauge showed 50 psi. but after a minute the pressure dropped to about 30 psi and the engine stumbled and died. This was a clue that the electric fuel pump was failing. A clogged filter would not give intermittent pressure changes.

I chocked the front wheel and made sure the parking brake was firmly set. I use at least two independent devices to hold up a vehicle that I'm getting under: in this case, a floor jack and one or more jack stands, also the parking brake was set. Jacks and jack stands do no good if the vehicle falls off of them. 

I raised and spread the load a little with a 2x4 on the floor jack. The two backup jack stands had a little weight on them to ensure the set up was stable and that they could not be bumped out of place. The correct jacking points were identified using All Data (available for free at the local library). Removing the spare tire gave more room to work. I disconnected the negative battery terminal. 

This inspection mirror was handy for seeing hard-to-reach things like these fuel connectors.

I siphoned the remaining fuel from the tank before removal. 

The following is a note of caution about working around gasoline. 

Gas vapor is heavier than air, and is very explosive. It sinks and pools and can travel long distances. It is important to not let gasoline fumes accumulate.  I avoid explosive-environment work indoors and ventilate religiously if I must.  I keep sources of ignition away from gas fumes.

I put aside the fasteners in a way that would remind me where they went when it came time to re-install them. 

I set up a fan at what I judged to be a safe distance away from the fumes, even though this work was outside.  I supported the front of the tank and lowered it until I could reach over the fuel tank and disconnect the hose from the roll over valve. The plastic vent hose connection tip on the roll over valve is easily damaged.

Moving the tank to a work area, I cleaned away as much dirt as possible to try to prevent it from falling into the tank. I still had to reach in and clean out some dirt.

The new pump installation was the reverse. ~Chuck