So my fuel pump went on my 01 2dr blazer. I replaced the fuel filter and dropped !y tank. I bought an AC Delco fuel pump off eBay. The pump will not sit flush with the supplied o-ring or the old one! The new pump is taller than the one I pulled off the tank. I have looked up the part number on top of the pump and I get mixed results between 2 and 4 door. The part number on top is mxmg 8732. Any help would be appreciated.

 

There is a difference in a 4 door and a 2 door pump for what reason God only knows.

 

2 door tanks are deeper and need a taller pump. Need to be very careful when buying on Ebay, many say they are name brand, or might use AC Delco part number, but are cheap China knock offs. 8732 is not an AC Delco part number.

 

I was afraid of that I'm going to get a refund then because I wanted an AC Delco pump. Any recommendations where to get a Delphi or AC Delco genuine pump.

 

Amazon & Ebay are both OK, you just need to read the description very carefully. There are a ton of scammers out there. AC Delco typically comes in a red, white & blue box with the AC Delco logo. AC Delco #MU1755 Generally will be in the area of $200. If you see something substantially less, it's probably knock off junk, stay away.

 

That's the thing mine came with the AC Delco box too.

 

Some of the scammers are very "creative". They've been known to switch boxes and put knock off junk in AC Delco boxes. Take your pump to an auto parts store and ask if you can compare a genuine AC Delco pump to the one you received. Look closely at numbers on both modules, and the fuel tank pressure sensor. The modules should be absolutely identical.

 

So I replaced the fuel pump and mocked it up temporarily. Started up then idled down and died. Won't stay running. Would not having the filler tube and vent hose cause it to do this? I have it jacked up in the back. I changed the pump and fuel filter and I'm ready to scream

 

In your first post you said the pump was bad. How did you determine that? This link explains how to diagnose it: https://blazerforum.com/forum/2nd-ge...eakdown-88305/
Post the numbers from all 4 tests and we can analyze them.

 

Pump did not turn on when key was turned in ignition