Wifes DD 1999 blazer z-2 died-fuel pump?test input needed.

[72'z'steve]

Hey guys I tried over at the Blazer forum but for some reason I can't get logged in??I know a few of you work on these wrecks.Anyway as title says my wifes money pit died this am. I was driving,sputtered and rolled to the side of the road,it would would restart then die.I heard the fuel pump run when keyed up it seemed.I had it flatbedded home [yikes] and threw a fuel pressure gauge on the fuel rail.zero,I don't hear the pump running on key up either.I did a fuel pump on this thing a year ago[I could wake it up with a rubber hammer] so I wasn't worried about diagnostics.I'd like to check for power to the pump but don't know if the harness is accessable in the rear.I also heard they burn up the plug on the module and they have a harness kit with the new pumps.Any help on where to test or opinions [other than replace the O2 LOL] would be MUCH appreciated!!! Later Steve!!!

 

[Mike N]

If it's a 4 door Blazer you can get to the harness without dropping the tank, the two door I can't remember. The plugs burn up on them because they were so small. The connector has four wires (gray, purple and two black), you're going to be looking for power on the gray one and ground on the black ones.

If no one is there to help you by cranking it over, you can pull the fuel pump relay out and jump pins 87 & 30 in the relay cavity. This will send a steady 12 volts to the pump. If it still doesn't run, smack the tank with a multi-angle swing press and see if you can wake it up.

If you do have to replace the pump get one with the updated four flat style plug, and make sure you solder/heatshrink the new harness in instead of the bs butt connectors they come with.

 

[whitesoxfbody]

The pumps are getting cheaply made, often Chinese. Especially if you get an aftermarket pump. But who can blame you when the "cheap" pumps are 175 smacks.
I've used the Delphi pumps and they are OEM. In fact, the last AC Delco pump I used had a Delphi pump inside the box. Delphi and Delco were somehow tied together years ago.
And the Delphi brand isn't too bad on price.

 

[72'z'steve]

Thanks Mike, I'll check out back [its a 2dr with the zr-2 wide axle package-won't fit on my dolly too ]I "remember" the harness running toward the back bumper when I did the pump but didn't know what to look for.I hit the tank with the bmfh and no wakey wakey,the fuel pump relay is located in/behind the glove box??or was that some other thing I was diagnosing on this wreck years ago.
Btw the fuel pump was a/c delco bought off amazon,was made in "Mexico" so I thought it was a good one!!!If anyones interested do a search in the archives I asked about the amazon parts and the "reasonable price" I don't know yet if thats the problem [I would bet tho] but I'll bleed for another locally this time.
Mike,of course the thing is full of gas [only 34 miles on full tank] can I snake a 3/8 or 1/2 hose down and siphon or pump out??I thought there was a "ball" in the filler or tank for spill prevention if you go rubber side up???
Again Thanks to all you guys are the best Steve!!!

 

[Mike N]

Fuel pumps never die on an empty tank. I've got a 97 Olds 88 with a dead pump/full tank waiting on my lift for me first thing tomorrow morning. Typical road salt infested piece of crap.... yay me.

Not sure if there's a check ball in the filler tube but you could always disconnect the tube at the tank and siphon from there if you can't get hose down the filler neck.

The relay may be under the hood on that one.

 

[whitesoxfbody]

Check that ground in the rear too before you drop it. It shares the same point as the lights. I've had issues before with those.
And Delco stuff has declined in quality a lot in the last few years. They're trying to compete with all the cheapy cheap stuff and the quality is suffering big time.

 

[Aceshigh]

I've often wondered why you can't just throw in a Walbro 255 lph instead.

Does it just pump too much fuel ??

 

[72'z'steve]

Aces,I remember seeing stuff on the walbro pump on the blazer forum but think there were mods for fuel regulation iirc,but I figured the original lasted 160 k and 12 years,the new should last at least half???I still can't get my computer to get the blazer forum up it just sits there with connecting and a little circle that spins[much like my head] gonna go out and pull the sheild and check some wires Later Steve!!

 

[dirtmod08]

I just replaced the pump on my 92 C1500 a couple weeks before I loaned it to my brother. Guess what? It came back home on a trailer last weekend. Preventative maintenance my ass, I just finished throwing the old one back in yesterday.

 

[gramps]

The airtex pump that autozone sells is made in Illinois. They just brought their mechanical division mfg back to il from Mexico. Only thing they have left from outside the US is some electrical pumps, however all pump assy's/modules are made in il.