SO. First no start that doesn't have anything to do with passlock! Ok thats all the good news I can pull out of it. Blazer drove fine all night. Park it, come back 1 hour later, go to start it, no go. It has good power, tries to turn over, engine shakes, blazer shakes, but no click roar.

I have been have to let the fuel pump prime up for a second or two on cold mornings in the last 2 or 3 weeks, but no problems other than that. Till tonight.

So I know a fuel pressure test is in order, doing that tomorrow AM, but if I get no/low pressure, how do I isolate the fuel pump vs a blown relay? Can I switch around relays in fuse box? Also remember I have the body lift, so the top of the fuel pump is accessible..any voltage test I can do there to see If the relays and everything are good, and its just the pump? I would guess it should have 12v across it?

tl;dr : truck doesnt start, feels like low/no fuel pressure. will post tomorrow with pressure results. how do i check pump vs relays? Whats voltage at pump supposed to be?

not to mention I just filled up 20 miles ago..and the blazer is on a street by campus...I can roll into my buddies apartment parking lot for a swap...but...not going to be enjoyable

 

Got it started! A few whacks to the fuel pump apparently freed it up. A few searches on here seem to show that the brushes bind up? Either way, looks like I need a new fuel pump asap.

Now its sitting in my driveway, with 17 gal of fuel [&o]

 

At least you could reach the pump without dropping the tank....

 

Yesss...The body lift makes working on everything a little bit easier

 

Ah, yes, the old whack test! I concur with the bad pump diagnosis. Change the fuel filter, too. I bet you'll havethe 'little black specks' in it from the brushes.

 

I had little black specs when I changed the filter 12-15k miles ago, just not very many..I actually thought at the time that it was filter material that was coming out after I dropped it on the ground

Any guess on life left in the pump? I'm going to try starting it later tonight when I get home...if its 0 pressure again, I'll chalk it up as dead [&o]

 

So...It had been starting up fine since getting it home originally...and it was driving fine after the start (I was driving through the neighborhood to heat it up, then parking and taking my dad's truck)...so I figure, hey Ill burn some gas off, and drive it to work.

Starts and drives fine, park it at 7:45am. Get off for lunch at 1 pm, no start. Bang on the tank a bit, still no go. Shes dead [&o]

$80 tow later, shes back in the driveway, getting a new pump on Monday (hopefully). Just gotta find a good one

btw...towing coverage on your insurance is awesome!

 

Finally replaced it today. Ive missed the blazer

Took a few hours, almost broke the vent tube at the tank, and my right hand on the transfer case (wrong size wrench on the fuel filter)..but other than that, pretty smooth.

One thing to note for anyone looking at replacing their pump:


DO NOT forget to disconnect this guy at the front of the tank. I only found one or two threads mentioning this hose regarding dropping the tank. Its a tiny hose...looks easily breakable.

 

A few months ago when I first got my blazer, my CEL kept coming on with a vacuum leak code, couldn't figure out where it was leaking til I dropped the tank (only reason I dropped the tank is because it was leaking). When I dropped my tankI noticed thevent valve was already broke. I'm guessing whoever dropped the tank before didn't disconnect it first. I had to get the vent valve at the Chevy dealer cost me $20(although you can get it from rockauto.com for $12, I didn't want to wait for it to get here). The funny thing is, I didn't know what the name of this piece was called so I took it to Autozone, Napa, Advance and a few others and NO ONE knew what this thing was. One place(I believe it was Napa)I went into, after I explained to them where this part was located they told me it was a sensor or something off the fuel pump...I automaticlly turned around and walked out the door and went to the Chevy dealer. Picked up my part the next day!!