So my blazer didnt start very well. It took several cranks to get it started. And seeming gets worse over time. My starter failed and was replaced with a brand new one. After installing the starter my engine started perfect on the first try. But later that day it was back to starting poorly. It will start much better with a charger on it, or will start by spraying some carb cleaner in the intake. I bought a pressure gauge and it reported low pressure, but a slightly different pressure every time i turn the key on. I have always smelled a gas smell from the hood after the engine was shut off. I replaced the fuel filter about a year ago. I can re-test the fuel pressure , but im sure that its higher with the charger on it so specify which way to test. The normal battery voltage is about 12.5, which is higher than the 12.25 v my s10 w/4.3 normall has, and the s10 starts perfect always.

So
#1 is this sure to be the fuel pump or more testing needed.
#2 where is the best place to get a fuel pump that wont need replaceing again in the next couple years
#3 i can only buy parts at autozone,orilies,advance or napa parts stores
#4 tell me again not to buy the $20 one from ebay, my billfold really wants me to.
#5 do any of the stores i mentioned sell just the fuel pump without the assembly ?

Thanks, dave.

 

First of all, what are you working on? Year at a minimum.

If you have confirmed low fuel pressure, it could be a result two things (either separately or combined). Low fuel pressure could be a result of a weak fuel pump. Higher voltage will mask a weak pump for a time. Also, if you have a leak in the plenum, it can cause a low pressure issue that will be combined with the pressure bleeding down to next to nothing over time.

Your engine, regardless of year, requires >55psi to start (60psi is what the book says) and the pressure should remain above 50psi 10 minutes after the pump has shut off.

The cost of the pump will depend on what year you have. For the '95-'97 (I think) models, the sending unit is separate from the pump so you can get just the pump which will save some coin. The later models, the pump is integrated into the sending unit. There are some cheaper kits on eBay that some people have tried, but I have never heard back from anyone regarding how it turned out for them down the road. Above all else, remember this. AC Delco or Delphi pumps only!

 

this is a 1997 chevy blazer 4x4 4.3L 4DR

 

My 1997 4X4 4-dr had an all-in-one assembly in which the pump could not be separately serviced. The Delphi brand pump cost me $350-$400.

Many mechanics in my area who have done a few of these fuel pumps don't like anything but Delphi or AC Delco pumps, because they say that any of the aftermarket pumps from Advance, Autozone, or Napa are so unreliable. A couple of different places told me that they have had aftermarket pumps go bad in as fast as a week, although they said most often you'll get a year out of them and that's about it. I guess you really get what you pay for.

Stupid question...have you replaced your fuel filter recently (as in within the last couple of months or less)? The filter can become plugged, as just happened with mine. If you've never done it on your Blazer before, do it now (especially if replacing your fuel pump). It's a commonly neglected item on vehicles; so if you haven't done it, who knows if/when the previous owner ever did.