Hey guys, so like a couple weeks ago, after work one day, my Blazer didn't start. So I cranked it a little, cranked it a little more, nothing. Waited about 10 minutes, cranked, and baboom, it starts.

So, the next day on my way to work, I was going 60 like normal, and all of a sudden it starts bogging and is up to 2.6 grand instead of the normal like 1900, or whatever. Stopped after a minute or so then went back to normal.

After work that day, went to start my Blazer, cranked, and nothing. Waited, cranked, nothing. And so on and so forth...

While outside work, tried some things. I pounded on the fuel tank while my friend cranked it, nothing. Checked relay, good. Outside my work was noisy so I couldn't hear if the fuel pump was turning on or not, so after a while, I gave up.

Once I got her towed home, I decided to try some more stuff to diagnose it.

I don't believe I heard the fuel pump start up at all when having my friend turn the keys forward.

Don't have a fuel pressure gauge, so after I cranked it a couple times, I pushed a screwdriver into the schrader valve, and a couple drops of fuel shot out. (I've never done that before so I do not know if a couple drops is good or bad. I'd assume bad.)

Later that day I checked if I popped a code or not (since my check engine light is always on since I deleted the rear O2 sensor). It popped the code for low fuel pressure or secondary ignition system failure, or something like that.

Also, my Blazer may've been on low fuel, but I believe my fuel gauge has been acting up.

And I've been Google'ing and stuff for a while, and not sure if this is 100% my fuel pump or not.

Thoughts?

-Recap:
Cranks but doesn't start.
Can't hear fuel pump start.
Relay is good.
Couple drops come out of schrader valve after cranked.
Pounding on fuel tank while cranking doesn't work.
Bogged a bit the last time it was running.

Thanks guys.

 

yep sounds like the pump. Which isnt uncommon on these blazers.

So now that you have to replace it,please do yourself a favor and buy only a ac delco pump,yea...its going to be a couple a hundred bucks but at least you wont be dropping the tank and replacing the aftermarket pump (hence the awesome lifetime warranty) every 2-3 months,or days. Delphi brand is ok,but anything else but the 2 is a no no.

 

Yeah, that's what I assumed.
And that's also what everyone has been saying, that the fuel pumps go. And I forgot to mention that it's at 105k miles which I've been told every 100k or so they go.

Then also yeah, I've had a discussion about fuel pumps with a couple guys at O'Reilly Auto. They were insistent upon not needing OE.

 

Rent a fuel pressure tester from one of the auto parts stores. Key ON, engine OFF, fuel pump running, (if it will) pressure must be 60psi to 66psi. It must remain above 55psi for at least 10 minutes after the pump shuts off. If the pump does not come on when you first turn the key to on, install a fused jumper wire from battery positive to the pump prime connection right next to the fuel pump relay. If it still doesn't come on, check for voltage and ground at the pump module connector. This thread will help you diagnose it: https://blazerforum.com/forum/tech-a...agnosis-23038/

EDIT: AC Delco or Delphi only when it comes to a pump. Don't EVER trust a parts salesman, better to ask someone that knows

 

Thanks for the reply.

And one last thing I just remembered...

Could it be a clogged fuel filter that would be the culprit of this? (Assuming I'm a moron and my fuel pump is fine)

EDIT:

Yeah, I wasn't falling for his salemanshipness, but merely laughing at how insistent he was.
I've been told numerous times to go OE for certain things like a fuel pump.

 

Could possibly be a filter, but to restrict fuel flow that much, the pump would most likely be screaming!

 

Is there the slightest chance that being on low fuel can make your vehicle bog?

EDIT:

Basically, my question, is... Am I a complete moron for not putting in a couple gallons of gas? It was on E and my vehicle had been sitting out in the direct hot sun for 8 hours. I wasn't sure if bogging could be a side effect of nearly empty. Now, when I hit the tank or try and jar it, there sounds like there's no fuel in there.

EDIT EDIT:

Put like 3-4 gallons in, tried to jump start, nada.
Only like a drop or two dribbled from the schrader valve again. Yippee.

 

If the pump sucks air, obviously the engine will stumble or stall depending on how much air it sucks. There's a myth about running low on fuel overheats the fuel pump, not so. The return fuel line empties fuel directly into the pump motor well in the fuel pump module so if the engine is running, the pump is being cooled. Keep in mind that when the tank runs low, there is a higher concentration of dirt that the pump could injest, if there's dirt in the tank

 

Well, does a pump fail from too much dirt in it? If so then sadly that is definitely the case as to why mine failed (assuming it did).

Being poor, I always go from paycheck to paycheck, and money to always top off my tank isn't there usually, so I run her into the ground.

 

There's a sock filter on the pump that catches the big chunks, but yes, too much dirt can destroy the pump. Original pumps usually last 100K miles, above that, consider it a gift