Alright, first I can't afford to miss work so I need to get this taken care of TODAY.

For the past couple months, after sitting overnight, my blazer (1998 4dr 4wd) would take a minute to start in the morning (I live in AZ so it's not cold). Usually I would have to crank it a couple times, pull the key, put the key back and bam it would start like nothing was wrong. Yesterday I had to do that almost 5 times, and today it won't start at all after trying on and off for 15 minutes.

Recent tune up a couple months ago (plugs, wires, cap, air filter).
I can hear the fuel pump
I pressed the valve in and there is fuel
I hooked up my pressure gauge and put the key on, and it reads 50psi.

I know it should be 60psi, would that 10 psi difference really cause it NOT to start? I don't have a ton of $ to throw around here on a fuel pump if it doesn't need it. What would you suggest?

 

I believe you need at least 55 psi to start the engine. Could be a fuel pump or a FPR. Have you kept track of the pressure after you get it started, or see how fast it drops after you turn the engine off?

 

Since I can't get it started, I can only get the pressure with the ignition on, I can see how fast it drops when I switch the key off from accssory. brb.

 

IIRC, 52psi is the minimum pressure for actuation of the poppet nozzles.

 

It stays at 50psi, when I pull the key it still reads 50psi, but when I try to start it, it drops to 40psi when cranking.

So since this reading is before the pressure regulator, I should go for the fuel pump? Everywhere I've read says it should be reading 60-66 psi.

 

Reading should be between 55psi and 60psi. The regulator is in the loop, but since the pressure doesn't bleed down, I doubt the regulator is at fault.

Have you replaced your fuel filter yet? That might be the first thing to do...

 

Yea, I did replace the fuel filter about a month ago (forgot to mention that). I'm sick, tired as hell, and have to take care of this!

The pressure does not bleed down, but I'll probably just replace the regulator anyways, I have 137k on this beast!

 

Well, that is one way to go about it...

I would check to make sure that it isn't a corroded power or ground wire to the pump by pulling the electrical connection at the pump and testing power/ground there. If you are not getting full battery voltage to the pump, it could explain the reluctance to starting...

Here is another functional test. Disconnect the MAF sensor and the intake plumbing from the top of the throttle body. Then pour some fuel down into the intake and see if you can get it to start and run (or die).

 

My discounted price on a whole complete module (pump, sender, float) is $322.

Holy Crap, didn't think they cost THAT much after discount.

 

After I add some fuel (what, like a cup?) down the tbody, do I hook the intake pipe etc back up before trying to start it?


Ohh, and appearantly there are 2 different fuel pumps, So I need to find out if I have an 18 gallon tank or a 19 gallon tank.


Man, this is turning bad quick.