2001 blazer /wont start

[steveb2001ZR2]

Ok 3 weeks ago Put new AC delco fuel pump, Replaced filter,blazer has 107,000 miles,was going to make a left hand turn, engine just quit, when I went to turn it over, it seemed to turn over real rough, when I say rough, I mean, the blazer shook, like it was falling apart, had it towed home, I tried it again, seems to turn over smooth now, But I now dont hear the fuel pump kicking on, My ? is , could it maybe one of the sencors, not letting the pump kick on?, I have been told sometimes them go out and the pump dont kick on?,will A tech 2 tell me this ?
after 650.00 for the pump and 150.00 for ABS sencors, Iam running out of cash here.
thank god the dealer give me the pump for 500.00. you just have to ask them guys if they can do better then that for the price.
HELPPPPPPPPPPPPPP

[MT-2500]

Check the pump for running.
Key on prime up and engine cranking.
If pump runs check fuel pressure.
Post back fuel pressure reading
Does it have good hot blue spark to all spark plugs?

[steveb2001ZR2]

Have not had time to check anything yet, just had it towed home, and had wife get in the turn key to see if I heard pump run, it didnt kick on, If I understand right, when some of them sensors go bad they wont let the pump run?, Iam going to get it inside fri. and check grounds, from when I did the fuel pump, I dubble checked everything, I have always been good about that.
will post as soon as I get time to work on it.

[MT-2500]

To see if sensors are working.
Check for good hot blue spark to more than on plug.

If good spark check fuel pump fuse and jumper fuel pump to see if it runs.

[steveb2001ZR2]

pump not running, as stated before, No fuel pressure, good spark,
took the relays, and changed them around( there is like 5 the same part mumber) no go, still no start or cant hear pump kick on.
checked for codes with one of them cheapys from auto zone, no codes

[MT-2500]

Pump circuit do not set codes.
When checking for spark always check more than on plug for spark.
Check fuse power to relay.
With a fused Jumper wire jump fuel pump gray feed wire to check pump.
Does pump run jumpered?

[steveb2001ZR2]

check fuse power to relay??, not sure I understand that one.
jump fuel pump gray feed wire?,where would this wire be, ?
Iam hopeing I dont have to pull that tank down again, wasnt a bad job, just would hate to start taking this thing back apart.

[MT-2500]

Proper testing before throwing parts at it or droping tank again.

Go to fuel pump relay.
Check for key on power to it.
Jumper gray fuel pump feed wire at relay and see if pump runs.

[steveb2001ZR2]

Jumper gray fuel pump feed wire at relay?? where is this wire to be found?
jump from ?gray wire to what?where relay plus in? Iam lost, and not understanding you, maybe more detail?
just asking where this wire is, because, the olny gray wire I remember is on top the tank, and on the blazer you have to take tank down to get to wires on top.
if you can do this from under the hood , then need to know where that wire is?

[MT-2500]

Originally Posted by steveb2001ZR2

Jumper gray fuel pump feed wire at relay?? where is this wire to be found?
jump from ?gray wire to what?where relay plus in? Iam lost, and not understanding you, maybe more detail?
just asking where this wire is, because, the olny gray wire I remember is on top the tank, and on the blazer you have to take tank down to get to wires on top.
if you can do this from under the hood , then need to know where that wire is?

The whole idea here is to apply 12 volts power to the fuel pump to see if the fuel pump runs.

The gray wire that powers the fuel pump runs from fuel pump relay all of the way to the fuel pump in tank.
It should have 12 volts on it key on 2 second prime up or engine cranking or engine running.

To test for fuel pump to see if it will run you can hook a 12 volt fused hot wire from battery pos. to the gray wire at any place from relay to the fuel tank.
Also
Check gray feed wire at relay and at the 4 wire plug in to the fuel tank close to fuel tank.

You will see it on the underside of fuel pump relay in under hood fuse box.
Also there should be a fuel pump prime/test connector at or near relay or fuse box.
It will be a single wire with a plastic end gray/white/black/red that is not connected to anything.
The other end will be tied to the gray fuel pump feed wire.
This can be used for testing for 12 volts to fuel pump and also for jumping 12 volts to fuel pump for testing.
Also check for 12 volts on the fused orange feed wire to fuel pump relay.

[steveb2001ZR2]

Ok I been working on it on and off all day, never did find where you can test it ,Iam sure its there must be tucked in the plastic around the wires, took relay box off , looked at it and said, hmmmm do I realy want to try to find this gray wire under here, and screw the box up or short it out, so I took tank down, No big deal, its easy, if you compare it to others, ok unhooked wire, had wife turn key, got my test light ,lite for the 4 sec.or so, tried this a few times, hooked back up beat on tank, pump not kicking on, took tank out, took pump out, now when I did this the first time, I tested the old pump, it did kick on, but since I had tank down, and pump dodnt run before, I replaced it, after getting it out, it had chuncks of dirt in it, this pump has 2 socks, one on outside and one inside the bowl it sits in, the one inside gets cut open, yes cut open, because of the spring holds this bowl down so hard it cuts it after some time, so all this dirt I say stopped the pump, my theory
anyway, once I got the now new pump out today and pumped in it would run, so off to the dealer mon.hope they take it back, now someone told me, maybe Iam not getting enough jiuce to the pump itself, here we go, how do check this????

[MT-2500]

VOLT/OHM METER READS VOLTAGE.
ALSO CHECK GROUND.
Good luck

[GLFarnes]

You need to go back through and read everything that MT-2500 told you and try all that. This guy knows what he's talking about so make sure you test for power at the relay with the key on and try jumping the connector like he said and the pump will run if the relay is bad.

GOOD LUCK!!

[steveb2001ZR2]

Ok heres what I got, I put 12 volts to the pump from an extra battery I got it didnt run- I got an new pump in the box that goes to a truck I have , I hooked it up, it ran, I did check for 12 volts @ plug that goes to pump it had 12 volts, says the volt meter, so Iam going to take pump back , because it dont run.
I have never had a pump go bad after replaceing it, but there is a first time for everything, I have been told they have been known to go bad ,that one lasted 3 weeks.
I thank you for all your help,Iam trying to learn these newer cars and trucks, and Iam ready to go back to the older ones,lol
Thanks guys for your help

[steveb2001ZR2]

First I want to say thanks for yoyr help, I took pump back the dealer didnt give me any lip about replaceing it, they did take it back and test it, came back said yep its bad, , it lasted 30 days, guy said he had never had one come back, so the Blazer is running again.
Guys Iam used to working on old cars, have restored a old Z28, did a old vette.
So when you start talking all that check this and check that you have to talk slow to me, I understand what you was saying about finding the gray wire, to jump relay, but I took that relay box off and I couldnt see any wires, now maybe you was wanting me to tack the bottom off, I wasnt to much on taking that apart, if I messed that box up , big money there, I do know what you was saying about the wire, coming out from the harnest, I have seen them before and used one on a 96 truck, But never did find mine. no big deal, it took a whole 30 mins. to drop that tank and check the pump from there.