Mechanics

CHEVY FUEL PUMP PSI RATING???

2000 Chevrolet Trailblazer

Engine Performance problem
2000 Chevy Trailblazer 6 cyl Four Wheel Drive Automatic 115000 miles

I just replaced the fuel pump, filter, and relay on my girlfriend's 2000 trailblazer. The filter was definitely clogged which I am guessing caused the pump to burn out. I could not find just a pump for sale, all the parts stores wanted to sell me the complete sending unit with pump included for $319+ I got a pump only from napa for $42 but it is for a 94 blazer. The pumps look identical, and the guy at the counter said they both have the same psi. I was told by a mechanic that on the newer trailblazers, if there is not enough pressure that the computer will not allow the fuel injectors to work, is this true? What is the recommende psi for a 2000 trailblazer? Everything has been hooked up properly, there is pressure in the fuel rail, the pump works, but fuel is not getting to the injectors. It starts if I dump some gas down the throttle body and will run untill that is burned off. Is there something I am missing like maybe a reset switch somewhere? All the fuses are good, and the pump is working great, just not the fuel injectors. The " spider" as ive heard it called does not leak, so I doubt that is the problem. Any info would be greatly appreciated, I am totally stumped on this one. I should also add that the truck has a 4.3 V-6 with the W code in the vin#
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Osrclint74
July 6, 2009.



The fuel pressure should be 60-66psi

Rasmataz
Jul 6, 2009.
The replacement pump I put in is only 9-17psi rating. What if I was to put in a pump that is rated 70-95psi? Would the fuel pressure regulator cut the pressure back down to the required amount? I am just trying to steer away from the $319+ one that includes the pump and the sending unit because I have no use for a replacement sending unit. I did find a replacement pump that is for a 2000 trailblazer, but it says the psi rating is 70-95. Even when I looked on the autozone website, their replacements that are the sending unit and pump all say the same, 70-95psi. Correct me if I am wrong, but isn't that the purpose of the fuel pressure regulator, to regulate the psi? So if I was to get the 70-95psi replacement pump, I should be ok right?

Tiny
Osrclint74
Jul 6, 2009.
Dont let someone fool you into thinking that you can put the fuel pump from an older model blazer into a newer model. The guy at the parts store told me that a pump from a 1991 blazer would work just fine, guess what, it didnt. My 2000 blazer requires 55-64psi according to the manufacturer specs. I put in a pump for a 1991 and it only gives out 9-17psi, not even enough to make the engine sputter or hiccup. After getting the proper pump online for a total of $34 and installing it into the old sending unit, the truck runs perfect, and I saved about $300 because I didnt need to replace the sending unit. Thanks to all who helped with this problem.

Tiny
Osrclint74
Aug 19, 2009.