Fuel Injector Voltage Question

[TOENY1967]

I NEED SOME HELP GUYS/GIRLS...
BOTH FUEL INJECTORS GET POWER TO THEM,, WE HAVE SWITCHED THE WIRE HARNESS, ONE SIDE WORKS PERFECT AS FAR AS THE INJECTOR SPRAYING, THE OTHER DOES NOT..
BY READING ON HERE I AM THINKING ITS THE 5 VOLT GROUND DEAL....
WHERE IS THIS 5 VOLT GROUND, AND /OR CAN I SPLICE OFF THE GOOD SIDE ??

THANKS..
IF I AM NOT BEING CLEAR WITH THIS LET ME KNOW OR EMAIL ME PERSONALLY AT [email protected]
BY THE WAY ITS A 91 BLAZER 6 CYL4.3

[amac209]

check the wiring. the injectors are fired by a ground pulse to one of the wires. i'm guessing this wire is open somewhere between the injector and the computer if you tear into the harness you'll probably find an open somewhere. check the connector at the computer too if you have continuity for all the wires from the computer to the injectors the computer is bad. if you get to the computer without finding an open try giving the computer a good smack most of the time this temporarily fixes them. good luck

[quaddriver]

Originally Posted by TOENY1967

I NEED SOME HELP GUYS/GIRLS...
BOTH FUEL INJECTORS GET POWER TO THEM,, WE HAVE SWITCHED THE WIRE HARNESS, ONE SIDE WORKS PERFECT AS FAR AS THE INJECTOR SPRAYING, THE OTHER DOES NOT..
BY READING ON HERE I AM THINKING ITS THE 5 VOLT GROUND DEAL....
WHERE IS THIS 5 VOLT GROUND, AND /OR CAN I SPLICE OFF THE GOOD SIDE ??

THANKS..
IF I AM NOT BEING CLEAR WITH THIS LET ME KNOW OR EMAIL ME PERSONALLY AT [email protected]
BY THE WAY ITS A 91 BLAZER 6 CYL4.3

plug in a noid light first and check for flash before we blame the ECM or quaddrivers

[TOENY1967]

Originally Posted by quaddriver

plug in a noid light first and check for flash before we blame the ECM or quaddrivers

WE KNOW WE ARE GETTING POWER, AT LEAST THE 12 VOLTS...
YOU THINK THE ECM, MIGHT BE IT? IS IT COMMON?

[quaddriver]

Originally Posted by TOENY1967

WE KNOW WE ARE GETTING POWER, AT LEAST THE 12 VOLTS...
YOU THINK THE ECM, MIGHT BE IT? IS IT COMMON?

the injectors are energized whenever the key is turned on. What the ecm does is supply a ground in order to fire them. the "'noid light" is a little tool that will flash each time the ECM supplies a ground, its an easy way to test for at least the wiring being intact.

if the harness fires, but the injector does not, then you have a problem with the injector itself or fuel lines leading to it

[TOENY1967]

Originally Posted by quaddriver

the injectors are energized whenever the key is turned on. What the ecm does is supply a ground in order to fire them. the "'noid light" is a little tool that will flash each time the ECM supplies a ground, its an easy way to test for at least the wiring being intact.

if the harness fires, but the injector does not, then you have a problem with the injector itself or fuel lines leading to it

ok, now you got me.... what exactly is a noid light your referring to, is it just a voltage tester?

[quaddriver]

Originally Posted by TOENY1967

ok, now you got me.... what exactly is a noid light your referring to, is it just a voltage tester?

no, it is a little plastic doohickey with a high intensity LED in it and a resistor and a plug that will fit the harness, there are about 6 common ones, you can buy them as a set (mac tool makes the set I have) but you can 'rent' them individually from autozone