fuel preasure problem video
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
fuel preasure problem video
Did some test today with the fuel preasure.
I test my fuel preasure before and it was not doing this. is not holding preasure.
here is what happend
key to on position the fuel pump start for 3 to 5 seconds. giving preasure to the fuel rail (40 to 42 psi) after the fuel pump stop. fuel preasure go down to cero (0) inmediately.
test the injectors wires Iam getting 12 volts to all injectors all the time. so injectors are open all the time. so whem the fuel pump stop. all the preasure scape true the injectors. because they are open
disconect all the injectors and the preasure hold ok with out a problem.
but since I have 12 volt all the time when the key is in on position if I connect any injectors. i loose all the preasure inmediately.
here is a video I took this afternoon. let me show you what iam talking about.
http://s1111.photobucket.com/albums/...4-14-23-29.mp4
I dont have to say i have no start condition.
I have test my fuel preasure before. and what happend was every time I turn key to on position fuel pump start for about 4 to 5 seconds. giving preasure to the rail. and the preasure hold after that.
I test my fuel preasure before and it was not doing this. is not holding preasure.
here is what happend
key to on position the fuel pump start for 3 to 5 seconds. giving preasure to the fuel rail (40 to 42 psi) after the fuel pump stop. fuel preasure go down to cero (0) inmediately.
test the injectors wires Iam getting 12 volts to all injectors all the time. so injectors are open all the time. so whem the fuel pump stop. all the preasure scape true the injectors. because they are open
disconect all the injectors and the preasure hold ok with out a problem.
but since I have 12 volt all the time when the key is in on position if I connect any injectors. i loose all the preasure inmediately.
here is a video I took this afternoon. let me show you what iam talking about.
http://s1111.photobucket.com/albums/...4-14-23-29.mp4
I dont have to say i have no start condition.
I have test my fuel preasure before. and what happend was every time I turn key to on position fuel pump start for about 4 to 5 seconds. giving preasure to the rail. and the preasure hold after that.
Last edited by hitmanpty; Jul 14, 2012 at 07:17 PM.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
the inj harnesses have 12v with key on, correct. but it only completes the circuit in the inj coil when ecm grounds one wire. normally.
looks as if the harness connectors are shorted to ground, either in ecm or elsewhere. if you use a test light from one harness plug terminal to the other, key on, it should not light, as I mentioned before. if it does, one wire is grounded.
that's how I believe it works, pty. may be wrong.
you may have only one harness plug grounded. you can check them with the light, as I said, one each side. if you have a light it points to ecm, says the book.
*** test light is what I mean, a "probe light", not the noid light that simulates the injector coil. probe each terminal in a harness plug connector to ground, one at a time, key on
looks as if the harness connectors are shorted to ground, either in ecm or elsewhere. if you use a test light from one harness plug terminal to the other, key on, it should not light, as I mentioned before. if it does, one wire is grounded.
that's how I believe it works, pty. may be wrong.
you may have only one harness plug grounded. you can check them with the light, as I said, one each side. if you have a light it points to ecm, says the book.
*** test light is what I mean, a "probe light", not the noid light that simulates the injector coil. probe each terminal in a harness plug connector to ground, one at a time, key on
Last edited by joe paco; Jul 15, 2012 at 08:10 AM. Reason: clarity: ***
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
[QUOTE=joe paco;1581315750]the inj harnesses have 12v with key on, correct. but it only completes the circuit in the inj coil when ecm grounds one wire. normally.
what is inj coil and can you explaind a little more this idea.
what is inj coil and can you explaind a little more this idea.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Do all this AGAIN and wait for the pressure to drop all the way DOWN to ZERO. DO NOT CRANK the STARTER,.
pull the spark plugs. IF ANY are wet......you need NEW injectoirs.
IF NO plugs are wet, you need NEW PUMP.Smell the fuel regulator...if its vac hose has gas...get a new one. If it does not have gas it is ok,.
easy.
pull the spark plugs. IF ANY are wet......you need NEW injectoirs.
IF NO plugs are wet, you need NEW PUMP.Smell the fuel regulator...if its vac hose has gas...get a new one. If it does not have gas it is ok,.
easy.
Advanced
Joined: Jun 2012
Posts: 89
Likes: 3
From: Zimmerman MN
You should not have power AND ground at the injectors with just the key on. You said all injectors have 12v power with the key on, but do they all have ground too? If so, you have a shorted wire or a bad ECM.
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Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
Do all this AGAIN and wait for the pressure to drop all the way DOWN to ZERO. DO NOT CRANK the STARTER,.
pull the spark plugs. IF ANY are wet......you need NEW injectoirs.
IF NO plugs are wet, you need NEW PUMP.Smell the fuel regulator...if its vac hose has gas...get a new one. If it does not have gas it is ok,.
easy.
pull the spark plugs. IF ANY are wet......you need NEW injectoirs.
IF NO plugs are wet, you need NEW PUMP.Smell the fuel regulator...if its vac hose has gas...get a new one. If it does not have gas it is ok,.
easy.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
I remeber yesterday. the car was running. I was doing some pulse test on the injector wires. everything was ok. into i get to wire number 8. I was using a regular test light
the wire on the test light have an alegator clip at the end. and i put a paper clip there for easy to insert on the injector wire.
so there i was. with one end inside the ijn. wire I was ready to put the other end of the test light to cheque for pulse. and acidentaly i drop the test light. wish hit metal par on the motor. o guest was ground. imeditale the car stop. and never start again.
now i can not check pulse. since I think my starter motor fail again. (i sure have to get a new one) but iam getting voltage to injector with the key on. since the injectors are open all the time. making my fuel preasure drop
Iam thinking. maybe i fried something with that acidental choke. need to find out what is damege and why I keep geting continue voltage to injectors
the wire on the test light have an alegator clip at the end. and i put a paper clip there for easy to insert on the injector wire.
so there i was. with one end inside the ijn. wire I was ready to put the other end of the test light to cheque for pulse. and acidentaly i drop the test light. wish hit metal par on the motor. o guest was ground. imeditale the car stop. and never start again.
now i can not check pulse. since I think my starter motor fail again. (i sure have to get a new one) but iam getting voltage to injector with the key on. since the injectors are open all the time. making my fuel preasure drop
Iam thinking. maybe i fried something with that acidental choke. need to find out what is damege and why I keep geting continue voltage to injectors
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Each injector has a coil of wire inside it. It makes a magnetic field that causes the injector to open.
The 12 volts for the injectors comes through the INJ1 and INJ2 fuses through the pink/black wires. When you unplug one injector connector and measure both wires you are actually measuring through the other 7 injectors and will see 12 volts on the light blue or light green wire also. If you unplug ALL 8 injectors, then you will NOT see the 12 volts on the light green or light blue wires.
The 12 volts for the injectors comes through the INJ1 and INJ2 fuses through the pink/black wires. When you unplug one injector connector and measure both wires you are actually measuring through the other 7 injectors and will see 12 volts on the light blue or light green wire also. If you unplug ALL 8 injectors, then you will NOT see the 12 volts on the light green or light blue wires.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
Each injector has a coil of wire inside it. It makes a magnetic field that causes the injector to open.
The 12 volts for the injectors comes through the INJ1 and INJ2 fuses through the pink/black wires. When you unplug one injector connector and measure both wires you are actually measuring through the other 7 injectors and will see 12 volts on the light blue or light green wire also. If you unplug ALL 8 injectors, then you will NOT see the 12 volts on the light green or light blue wires.
The 12 volts for the injectors comes through the INJ1 and INJ2 fuses through the pink/black wires. When you unplug one injector connector and measure both wires you are actually measuring through the other 7 injectors and will see 12 volts on the light blue or light green wire also. If you unplug ALL 8 injectors, then you will NOT see the 12 volts on the light green or light blue wires.
I had to perform the test a while ago to get myself back on track!
as he says, key on, all disconnected, one wire of each terminal, the pink/blk, will show a light on when probed to ground. the blue and green will not. is this what you have?
but, they should not show a light when probed to each other, unless engine is cranking and distributor is sending reference pulse to the ecm. if you test pink to blue or green, with all disconnected, and you show a light, there is a ground somewhere, as 1fatcat said..
joe
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
ok I will go and test again and come back
do i have to umplug the cool start injector also????. I will umplug it any way just to make sure
do i have to umplug the cool start injector also????. I will umplug it any way just to make sure
Last edited by hitmanpty; Jul 15, 2012 at 10:11 AM.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
Ok did more test like you guys say.
this are the conditions.
all inj. wires umplug. including the cool inj.
Engine off key off. the 2 prove from meter on wires . like in this picture. i get 0.02 volts in every inj wire
[IMG]
[/IMG]
Engine off key to on position the 2 prove conected to the inj wire. I get 12.20 volts. like show on the picture, in every inj wire
[IMG]
[/IMG]
engine off key to off position. prove negative to negative on batery positive to inj wire. I get 0.03 volts as show in pic
[IMG]
[/IMG]
[IMG]
[/IMG]
engine off key to off one prove to negative the other prove just move to the next ping on the same connector. I get 0.01 volts as show on pic. same happend for all the inj wire test under the same condition
[IMG]
[/IMG]
key to off position engine off. prove one to positive on battery. prove 2 to inj wire ping 1 and them move to ping 2. I get 12.61 and 12.63. in that orther here are the 2 pictures. same result for every inj wire
[IMG]
[/IMG]
[IMG]
[/IMG]
[IMG]
[/IMG]
this are the conditions.
all inj. wires umplug. including the cool inj.
Engine off key off. the 2 prove from meter on wires . like in this picture. i get 0.02 volts in every inj wire
[IMG]
[/IMG]Engine off key to on position the 2 prove conected to the inj wire. I get 12.20 volts. like show on the picture, in every inj wire
[IMG]
[/IMG]engine off key to off position. prove negative to negative on batery positive to inj wire. I get 0.03 volts as show in pic
[IMG]
[/IMG][IMG]
[/IMG]engine off key to off one prove to negative the other prove just move to the next ping on the same connector. I get 0.01 volts as show on pic. same happend for all the inj wire test under the same condition
[IMG]
[/IMG]key to off position engine off. prove one to positive on battery. prove 2 to inj wire ping 1 and them move to ping 2. I get 12.61 and 12.63. in that orther here are the 2 pictures. same result for every inj wire
[IMG]
[/IMG][IMG]
[/IMG][IMG]
[/IMG]
Racer
Joined: Oct 2002
Posts: 372
Likes: 1
From: Corunna Mi
You have a grounded or pinched wire on your injector harness. Look at your last three pictures. You have the Black negative wire of your meter hooked to the positive of your battery and the Red probe of your meter hooked to the harness. It reads -12.61 volts. If you leave everything else the same but place the red probe of your meter to the engine block instead of the harness you will still read -12.61 volts. You need to switch to the ohms scale on your meter and read from the ground Negative side of your battery. Key off.
Team Owner
Joined: Jan 2003
Posts: 20,315
Likes: 245
From: Summerland B.C. Canada
There should be no ground at injector harness at anytime, unless it is running.
You either have a short to ground in injector harness, or something screwed up in ECM.
With all injectors unplugged, set your meter to ohms and test for continuity between battery ground and light blue or light green of injector harness.
Post what you find.
You either have a short to ground in injector harness, or something screwed up in ECM.
With all injectors unplugged, set your meter to ohms and test for continuity between battery ground and light blue or light green of injector harness.
Post what you find.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
You have a grounded or pinched wire on your injector harness. Look at your last three pictures. You have the Black negative wire of your meter hooked to the positive of your battery and the Red probe of your meter hooked to the harness. It reads -12.61 volts. If you leave everything else the same but place the red probe of your meter to the engine block instead of the harness you will still read -12.61 volts. You need to switch to the ohms scale on your meter and read from the ground Negative side of your battery. Key off.
I agree -grounded blue/green wire or ecm fault. he shows 12v checking pin to pin in connector, when the blu'- green is not supposed to be grounded.
but how does he show 12v checking battery+ to pink/blk wire, which is apparently not grounded? what am I overlooking? is this another senior moment?
joe
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
There should be no ground at injector harness at anytime, unless it is running.
You either have a short to ground in injector harness, or something screwed up in ECM.
With all injectors unplugged, set your meter to ohms and test for continuity between battery ground and light blue or light green of injector harness.
Post what you find.
You either have a short to ground in injector harness, or something screwed up in ECM.
With all injectors unplugged, set your meter to ohms and test for continuity between battery ground and light blue or light green of injector harness.
Post what you find.
in wich of this number sure I put my selector to mesure ohme
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
ok I will do that. but i have to go to family lunch with my wife. i have to doit when i come back. .
what sure i spect from this test. what this test will tell me.
also how do i know if my ecm is gone bad. for sure
what sure i spect from this test. what this test will tell me.
also how do i know if my ecm is gone bad. for sure