95 Chevy Blazer (wont start) COLD

[DelCoch]

On the '95 W engine - there is a red fuel pump test wire located under the hood, on the drivers side inner fender, next to the black electrical junction box. It will be a red wire with a black or gray end and won't be connected to anything - just hanging there. Apply a 12v supply to this red fuel pump test wire and the fuel pump should run. (When you apply a 12V supply to the red fuel pump test wire it will by-pass all other electrical components in the fuel pump circuit)

If the fuel pump runs when applying a 12V jumper to the red fuel pump test wire, then check fuel pump pressure at shrader valve while pump is running. Pressure has to be above 60 psi for engine to start. If you have proper pressure, disconnect jumper wire and observe pressure drop, it should only drop 3-4psi. If it drops more than this the pressure regulator is probably bad.

If all the above checks out, then your pump is ok, in which case remove the jumper wire and with just the key turned on, conduct "A" and "C" below - (skip "B"). Remember, when the key is first turned on the pump only runs for 2 seconds and then the key must be off for 10 seconds before the pump will run for another 2 seconds.

If the pump doesn't run when a 12v jumper is applied:

(A) Disconnect the wiring harness at the fuel pump connector at the gas tank.

(B) Again apply a 12v supply to the red fuel pump test wire and leave it there while checking for current on the Grey wire at the fuel pump connector at the gas tank. You can check for current with a test light or volt meter, but in any case make sure you have a good ground when testing.

(C) If you have 12v on the Gray wire and the black wire is supplying a good ground and the pump doesn't run, make sure the connector at the gas tank is making a good connection. If pump still doesn't run, its toast and needs replaced.

For info on replacing fuel pump on a '95 Check out this Post

[DRIFT_PIG]

Originally Posted by MT-2500

I would suggest some proper testing on the fuel pump and fuel pump circuit first.

hey i need help just finish installing fuel pump and now the truck wont start any suggestion on it i think they gave me the s10 blazer fuel pump and mine is a 95 blazer ls 4dr 4.3 liter vortec v6 is ther a difference in fuel pump can this cause it not to start.

[MT-2500]

Originally Posted by DRIFT_PIG

hey i need help just finish installing fuel pump and now the truck wont start any suggestion on it i think they gave me the s10 blazer fuel pump and mine is a 95 blazer ls 4dr 4.3 liter vortec v6 is ther a difference in fuel pump can this cause it not to start.

Read post no 16.

[MT-2500]

Originally Posted by DRIFT_PIG

hey i need help just finish installing fuel pump and now the truck wont start any suggestion on it i think they gave me the s10 blazer fuel pump and mine is a 95 blazer ls 4dr 4.3 liter vortec v6 is ther a difference in fuel pump can this cause it not to start.

You need to give us some info.
Have you got spark to all plugs?
Have you got good 60 lbs of fuel pump pressure?
Does the fuel pump run on engine crank or key on 30 second prime?
If not check for 12 volts to fuel pump relay.
Orange wire. Off of fuse EMC/battery.
Or jump 12 volts to fuel pump With a FUSED JUMPER to the red fuel pump prime wire at relay or left rear of engine area.
Let us know how that goes.

[DRIFT_PIG]

we have 0 psi in the fuel pump pressure we attach it to shrader valve an got 0 pounds of pressure whats wrong
fuel pump runs when key is turn on for 3 sec and after crank runs for another 6 seconds
we jump the fuel pump at the red wire and it turns on we also replaced the fuel filter i need help it still does not run.
we also got the battery recharged and still didnt help

[DRIFT_PIG]

we have 0 psi in the fuel pump pressure we attach it to shrader valve an got 0 pounds of pressure whats wrong
fuel pump runs when key is turn on for 3 sec and after crank runs for another 6 seconds
we jump the fuel pump at the red wire and it turns on we also replaced the fuel filter i need help it still does not run.
we also got the battery recharged and still didnt help

[DelCoch]

After replacing the fuel pump and fuel filter it takes a little while for the new pump to deliver fuel to the shrader valve, as the fuel line and fuel filter are empty. How much gas did you put back in the tank after replacing the pump. You need at least 5-gallon with the truck sitting level, (not jacked up in the rear).

Remove the fuel filter and see if the pump is pumping anything at that location. If so, put your finger over the end of the line and see if it has any pressure. If no pressure you need to remove the fuel pump and check it.

Make sure the fuel filter is on right - it has arrows to indicate the direction of flow.

Let us know what you find.

[DRIFT_PIG]

ok ill check that asap