Two injectors wide open with key on
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Two injectors wide open with key on I am working on a "swap" ---Gen 4 in a 2000 Camaro with 4L80. I have a E38 computer, stand alone harness, external fuel pump with regulator set at 58psi. I can turn the key to ON, fuel pump runs and #7 and #8 cylinders will fill with gas in about 15 seconds. I can spin the engine over with the plugs out and it will spray fuel across the garage. Only on 7 and 8. I replaced #8 injector to see if I had a bad one. Same thing happens. How can they be locked on????
Before you go ripping out your wiring, Un plug those 2 and see if they still do it. I just went thru this, had a piece of trash holding open a pintle on one of mine.
I know you said you replaced it, but it would double check if it’s the wiring/ecu
esp. if the injectors your using have sat around for a while.
I know you said you replaced it, but it would double check if it’s the wiring/ecu
esp. if the injectors your using have sat around for a while.
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I've checked injectors before by lifting the assembly, putting a pan underneath, and having someone crank the engine while observing. Gives a better idea what's happening, and if you do have one sticking open, at least all that fuel isn't going into the cylinder potentially hydro-locking it.
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Thread Starter
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I've checked injectors before by lifting the assembly, putting a pan underneath, and having someone crank the engine while observing. Gives a better idea what's happening, and if you do have one sticking open, at least all that fuel isn't going into the cylinder potentially hydro-locking it.
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Verdad Gallardo Thread Starter
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Before you go ripping out your wiring, Un plug those 2 and see if they still do it. I just went thru this, had a piece of trash holding open a pintle on one of mine.
I know you said you replaced it, but it would double check if it’s the wiring/ecu
esp. if the injectors your using have sat around for a while.
I know you said you replaced it, but it would double check if it’s the wiring/ecu
esp. if the injectors your using have sat around for a while.
Here is a whole set for less than $100
I suspect that whatever injector you have, Bosch had nothing to do with them.
Andrew
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Genuine Bosch. I talked to the supplier and they said to send them back and they would check them out. I ohmed the coils and they are in spec, so it is something else. It could be trash from the new fuel lines. Only two plugs affected. I was careful to clean the lines as I made them, but -----.
As soon as I get them back, I will post results.
As soon as I get them back, I will post results.
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From: Bostwick, GA.
Unplug the fuel pump relay.
KOEO & with a VOM, or a NOID lite, check to see if there is a closed circuit across the 2 pins in the inj plug.
If no lite, the injs have STB and are stuck open.
If yes, then the ecm driver is shorted or the negative side of the harness is going to ground.
KOEO & with a VOM, or a NOID lite, check to see if there is a closed circuit across the 2 pins in the inj plug.
If no lite, the injs have STB and are stuck open.
If yes, then the ecm driver is shorted or the negative side of the harness is going to ground.
Thread Starter
10 Second Club
Joined: Nov 2005
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Thread Starter
10 Second Club
Joined: Nov 2005
Posts: 933
Likes: 75
Unplug the fuel pump relay.
KOEO & with a VOM, or a NOID lite, check to see if there is a closed circuit across the 2 pins in the inj plug.
If no lite, the injs have STB and are stuck open.
If yes, then the ecm driver is shorted or the negative side of the harness is going to ground.
KOEO & with a VOM, or a NOID lite, check to see if there is a closed circuit across the 2 pins in the inj plug.
If no lite, the injs have STB and are stuck open.
If yes, then the ecm driver is shorted or the negative side of the harness is going to ground.
If checking with a VOM, am I checking for a low voltage?
If the ecm driver was shorted, wouldn't that affect the other 6 injectors?
Thanks
Thread Starter
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Unplug the fuel pump relay.
KOEO & with a VOM, or a NOID lite, check to see if there is a closed circuit across the 2 pins in the inj plug.
If no lite, the injs have STB and are stuck open.
If yes, then the ecm driver is shorted or the negative side of the harness is going to ground.
KOEO & with a VOM, or a NOID lite, check to see if there is a closed circuit across the 2 pins in the inj plug.
If no lite, the injs have STB and are stuck open.
If yes, then the ecm driver is shorted or the negative side of the harness is going to ground.
With a VOM, KOEO, all of the injector plugs read 12 volts. I unplugged each one and checked across the two pin receptacles. There are ground wires on the harness that are connected to the head and frame. Do you mean that all of the injector ground wires are grounded to the engine ground? How to check the computer?? I don't understand why all of the inj's were not open like 7 and 8.
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From: Bostwick, GA.
"With a VOM, KOEO, all of the injector plugs read 12 volts".
ONE wire in each inj plug is HOT. ONE wire is not.
If you are checking the TWO inj harness pins with both VOM probes and you have 12V, then there's an issue.
NOTE that there are different color wires for the ground side and a common color for the 12V supply side, in EVERY inj harness plug.
Put 1 VOM probe, the RED one, on the common color wire and the other probe, the BLACK one, on a good ground.
NOT on the other harness wire. Get 12V? You should.
If you are checking across the 2 pins in the harness and are getting 12V, That means the inj harness negative side is either shorted to the engine or the PCM driver is shorted.
ONE wire in each inj plug is HOT. ONE wire is not.
If you are checking the TWO inj harness pins with both VOM probes and you have 12V, then there's an issue.
NOTE that there are different color wires for the ground side and a common color for the 12V supply side, in EVERY inj harness plug.
Put 1 VOM probe, the RED one, on the common color wire and the other probe, the BLACK one, on a good ground.
NOT on the other harness wire. Get 12V? You should.
If you are checking across the 2 pins in the harness and are getting 12V, That means the inj harness negative side is either shorted to the engine or the PCM driver is shorted.