94 fuel pump not working

[Chris Stewart]

Oh, stay with the stock rated fuse. It's possible the connector shorted while you were maneuvering the tank...I guess that's why they say "disconnect the battery" on every repair except a tire change.

[Blue Bowtie]

Originally Posted by Chris Stewart

I agree with jd-autotech, you need to be sure the wires going to the pump are hot, the fuel tank will need to be lowered..

Our most cool pals Old Master and Maxwedge have spoken often about using non-Delco/ Delphi parts.

In this case, I would advise AVOIDING the Delphi parts, or at least the older ones. The connector on the tank top unit is notorious for failures. The aftermarket came up with a replacement pump unit and connector about 8 years ago, and only within the last 2-3 years has Delphi itself now started supplying the same replacement connector set with their replacement fuel pump units. It took them just about as long as Toyota to confirm that they had a problem. Not all of them fail, but a substantial percentage (probably 15-20%) have problems. This is the case from about 1994-2003 units, and some of the later ones depending upon model.

The other thing to check is the ground connection near the tank since it is critical to proper pump operation. The ground connection is exposed to the elements in its location, and can corrode over time causing resistance. Less than 1 ohm can drop pump supply voltage enough to render it useless for making adequate staring pressure.

Incidentally, a 20A fuse isn't likely to help a thing unless the correct fuse is already blown. The pump doesn't need anything near that.

[RANT]

I often get a chuckle when I read comments about "original" parts, recalling how back in the good old days large numbers of people used to advise not using Bosch injection parts and sensors. If they only understood that Bosch was the OEM supplier to GM they might think differently. Delphi doesn't actually MAKE anything to speak of any more, and most of the majors have been sourcing their parts for decades now.

I used to work for a Tier II supplier to GM (and Ford, and Honda, and Nissan, and some of the others in little lots), and we would stamp thousands of parts with a GM, Delco (then Delphi), AC Spark Plug, and PED names and numbers. We even made valves for the later SBC, LS, Northstar, and Gen III Chevy V-6s (plus Honda internal engine fasteners, Nopar parts, Ford parts, Nissan parts, yada).

BTW - Don't ever use a Robertshaw PCV valve or radiator cap on a GM. They're probably not anywhere near as good...

The one advantage to using OEM branded parts is that they probably have to meet some level of SPC/QC and general standards. The raw aftermarket doesn't have to deal with that and can get away with being lazy at times. If you buy the lowest price Pacific Rim components you're probably going to get exactly what you paid for. If you buy good quality components, the name on the box is not as likely to matter. After replacing several dumpsters full of failed factory parts I would NEVER touch factory parts in some applications. Exploded planetary gearsets and deformed shells and drums in GM transmissions have taught me to find something better. Leaking intake gaskets to the point of class action suits, valve springs suitable for retractable ball pens, idler arms wearing out faster than the tires, camshaft billets snapping at the pump drive gear, timing sprockets with plastic teeth, and other failures should remind us that original isn't always best.

There are exceptions. For example, don't ever even think of using anything but an AC/Delco distributor cap for a later 262 V-6 or older Vortec V-8 unless it's an emergency and you only need to go 500 miles. The aftermarket just hasn't figured that one out, and can't seem to get the insulation epoxy right.

In short, don't condemn a replacement part by name. I can name probably as many parts from the factory with bigger problems, and it's possible that Walbro made the original pump anyway.

[/RANT]

[Chris Stewart]

That's why I listen to dealer line mechanics and hold them in great esteem.
They change out these parts for decades and often have to deal with home "fixes" including replacing inferior cheapo parts.
I am disgusted by engineering goof jobs like the plastic intake manifold gaskets and new venture/GM & Chrysler's inside joke transfer cases along with the other items you mention.

[old_master]

GM S & T body vehicles, (Bravada, Jimmy, Blazer, & pick ups) do not use an inertia switch, never have. Also, contrary to popular belief, if engine oil pressure drops to zero, the oil pressure switch WILL NOT shut off the fuel pump.

As mentioned earlier, circuits at the pump are critical. Unplug the fuel pump module electrical connector and check for battery voltage on the grey wire for 2 seconds when the ignition is initially turned to the RUN position. After 2 seconds voltage should drop to zero. It should show battery voltage continuously when the ignition is in the START position. The black wire must show less than 5 ohms resistance to a good, clean chassis ground at all times. Post your results.

[Chris Stewart]

What's the latest Fishingirl?