fuel preasure problem video
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
Put as simply as possible the inectors should have power whenever the key is on. The ECM provides the ground to make them fire. The best way to test for the ground signal from the ECM is to use a noid light, not a test light. Everything you are doing could be done in a few minutes with a noid light. Since you have new injectors I would suspect you are looking in the wrong direction anyway. Have you checked the fuel pressure regulator?
Last edited by aminnich; Jul 15, 2012 at 03:41 PM.
Burning Brakes
Joined: Aug 2006
Posts: 878
Likes: 2
From: BC
Put as simply as possible the inectors should have power whenever the key is on. The ECM provides the ground to make them fire. The best way to test for the ground signal from the ECM is to use a noid light, not a test light. Everything you are doing could be done in a few minutes with a noid light. Since you have new injectors I would suspect you are looking in the wrong direction anyway. Have you checked the fuel pressure regulator?
Do the fuel pressure test 3 times.
1, Do the test as you did before to confirm you still have a problem.
2, Test it with the return line pinched
3, Keep the return line pinched but this time as soon as the pressure has built pinch the feed line too.
Tell us the results from this.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
I agree - I would be testing the pressure regulator too.
Do the fuel pressure test 3 times.
1, Do the test as you did before to confirm you still have a problem.
2, Test it with the return line pinched
3, Keep the return line pinched but this time as soon as the pressure has built pinch the feed line too.
Tell us the results from this.
Do the fuel pressure test 3 times.
1, Do the test as you did before to confirm you still have a problem.
2, Test it with the return line pinched
3, Keep the return line pinched but this time as soon as the pressure has built pinch the feed line too.
Tell us the results from this.
Last edited by hitmanpty; Jul 15, 2012 at 10:58 PM.
Team Owner
Joined: Jan 2003
Posts: 20,315
Likes: 245
From: Summerland B.C. Canada
I agree - I would be testing the pressure regulator too.
Do the fuel pressure test 3 times.
1, Do the test as you did before to confirm you still have a problem.
2, Test it with the return line pinched
3, Keep the return line pinched but this time as soon as the pressure has built pinch the feed line too.
Tell us the results from this.
Do the fuel pressure test 3 times.
1, Do the test as you did before to confirm you still have a problem.
2, Test it with the return line pinched
3, Keep the return line pinched but this time as soon as the pressure has built pinch the feed line too.
Tell us the results from this.
Sorry we didn't get to hook up last weekend. You no answer your phone.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
Ok i did the test
this are the condition
car off key to off.
all the inj wire umplug
meter set to ohms 20k
negative prove to negative on battery
positive prove to inj wire pin 1 I get a reading of 1.94 ohms
positive prove to inj wire pin 2 i get a reading of 0.75 ohms
I did test the two pins on the inj wire since i dont know wich one is the correct one.
here are the pictures of the 2 test
[IMG]
[/IMG]
[IMG]
[/IMG]
forgot to preform the test in every other inj wires. but it was late . i asume the same condition in the rest of injectors
this are the condition
car off key to off.
all the inj wire umplug
meter set to ohms 20k
negative prove to negative on battery
positive prove to inj wire pin 1 I get a reading of 1.94 ohms
positive prove to inj wire pin 2 i get a reading of 0.75 ohms
I did test the two pins on the inj wire since i dont know wich one is the correct one.
here are the pictures of the 2 test
[IMG]
[/IMG][IMG]
[/IMG]forgot to preform the test in every other inj wires. but it was late . i asume the same condition in the rest of injectors
Burning Brakes
Joined: Aug 2006
Posts: 878
Likes: 2
From: BC
Sorry my bad - your right I didn't watch the vid!
Looks like you are either going to have to search for a bad wire or run 2 new ones. You could physically unplug the ECM connectors and re do the test above. I think the likely hood that the results will change are slim to none but it rules out the ECM at least.
If its as simple as a bad wire though its strange that its on both banks.
Looks like you are either going to have to search for a bad wire or run 2 new ones. You could physically unplug the ECM connectors and re do the test above. I think the likely hood that the results will change are slim to none but it rules out the ECM at least.
If its as simple as a bad wire though its strange that its on both banks.
Last edited by dan_t; Jul 16, 2012 at 12:12 AM.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
Iam syspecting bad ecm because the situation i describe early about the incidente where i acidentaly grond one wire went engine was runing .
Ok coming Back to this last Test i did . With ohms . What this test aré telling me about the problema.
Can some one explain
Ok coming Back to this last Test i did . With ohms . What this test aré telling me about the problema.
Can some one explain
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
This is the injector circuit, from the FSM, page 6E3-A-24:
The two injector fuses INJ1 & INJ2 only get 12 volts when the ignition switch is on ("IGN." in the diagram). The other side of the injectors (light green and light blue wires) is connected to ground inside the ECM by the "INJ. DRIVER". This connection should be OPEN when the ignition is off.
Since all the injectors are connected together, you only have to do the test on one connector. All the others will be the same.
Your reading of 1.94 is 1.94K, where K is 1000. In other words, it's 1940 ohms. That sounds too low to me. The only way to find out if the ECM is bad is to disconnect it and do the test again.
You might try removing the INJ1 and INJ2 fuses and see what readings you get with the ohmmeter. One probe on ground, the other on the connector pins. You should get a very high resistance (maybe "OL" for open -- some meters just have a blank display).
The two injector fuses INJ1 & INJ2 only get 12 volts when the ignition switch is on ("IGN." in the diagram). The other side of the injectors (light green and light blue wires) is connected to ground inside the ECM by the "INJ. DRIVER". This connection should be OPEN when the ignition is off.
Since all the injectors are connected together, you only have to do the test on one connector. All the others will be the same.
Your reading of 1.94 is 1.94K, where K is 1000. In other words, it's 1940 ohms. That sounds too low to me. The only way to find out if the ECM is bad is to disconnect it and do the test again.
You might try removing the INJ1 and INJ2 fuses and see what readings you get with the ohmmeter. One probe on ground, the other on the connector pins. You should get a very high resistance (maybe "OL" for open -- some meters just have a blank display).
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Instructor
Joined: Mar 2010
Posts: 216
Likes: 4
From: Shrub Oak NY
With the other injectors connected, when you ohm from minus of an injector plug to ground you are ohming the ground path through the ECM, the path it uses to control the injectors. That might be your 0.75 ohms which from what i've read here is a problem since the injectors will always be energized.
But when you ohm the plus side, assuming there is no connection to the fuse since the ignition is off, you are ohming the plus of the plug you have disconncted through the coils of the other 3 injectors then through the ECM control ground. I would disconnect the other 3 injectors which will make the readings clearer. Then you should see infinite resistance on the plus side.
I think the ECM controls the neg or ground side of the injectors so as to make it harder to damage the ECM so that if by mistake you ground one of the ECM ground control wires so what? its already grounding it through the ECM.
But when you ohm the plus side, assuming there is no connection to the fuse since the ignition is off, you are ohming the plus of the plug you have disconncted through the coils of the other 3 injectors then through the ECM control ground. I would disconnect the other 3 injectors which will make the readings clearer. Then you should see infinite resistance on the plus side.
I think the ECM controls the neg or ground side of the injectors so as to make it harder to damage the ECM so that if by mistake you ground one of the ECM ground control wires so what? its already grounding it through the ECM.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
This is the injector circuit, from the FSM, page 6E3-A-24:
The two injector fuses INJ1 & INJ2 only get 12 volts when the ignition switch is on ("IGN." in the diagram). The other side of the injectors (light green and light blue wires) is connected to ground inside the ECM by the "INJ. DRIVER". This connection should be OPEN when the ignition is off.
Since all the injectors are connected together, you only have to do the test on one connector. All the others will be the same.
Your reading of 1.94 is 1.94K, where K is 1000. In other words, it's 1940 ohms. That sounds too low to me. The only way to find out if the ECM is bad is to disconnect it and do the test again.
You might try removing the INJ1 and INJ2 fuses and see what readings you get with the ohmmeter. One probe on ground, the other on the connector pins. You should get a very high resistance (maybe "OL" for open -- some meters just have a blank display).
The two injector fuses INJ1 & INJ2 only get 12 volts when the ignition switch is on ("IGN." in the diagram). The other side of the injectors (light green and light blue wires) is connected to ground inside the ECM by the "INJ. DRIVER". This connection should be OPEN when the ignition is off.
Since all the injectors are connected together, you only have to do the test on one connector. All the others will be the same.
Your reading of 1.94 is 1.94K, where K is 1000. In other words, it's 1940 ohms. That sounds too low to me. The only way to find out if the ECM is bad is to disconnect it and do the test again.
You might try removing the INJ1 and INJ2 fuses and see what readings you get with the ohmmeter. One probe on ground, the other on the connector pins. You should get a very high resistance (maybe "OL" for open -- some meters just have a blank display).
first the picture cant see the picture on your post. but dont worry. I have the manual. and i found the page thank for the page number.
all the test I did was with the key to off and all the injectors unplug, including the cool start inj.
you say that my first reading is 1940 ohms. and is to low. what number is normal reading here. also 1940 ohms is this the positive side of wire or ground?
where is the inj1, inj2 fuse?
next step will be repeat the test with the ecm disconnected.
sure I disconect the 2 harnres from ecm?
is this test is with the key off?
i apriciate if someone help me with this questions.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
With the other injectors connected, when you ohm from minus of an injector plug to ground you are ohming the ground path through the ECM, the path it uses to control the injectors. That might be your 0.75 ohms which from what i've read here is a problem since the injectors will always be energized.
But when you ohm the plus side, assuming there is no connection to the fuse since the ignition is off, you are ohming the plus of the plug you have disconncted through the coils of the other 3 injectors then through the ECM control ground. I would disconnect the other 3 injectors which will make the readings clearer. Then you should see infinite resistance on the plus side.
I think the ECM controls the neg or ground side of the injectors so as to make it harder to damage the ECM so that if by mistake you ground one of the ECM ground control wires so what? its already grounding it through the ECM.
But when you ohm the plus side, assuming there is no connection to the fuse since the ignition is off, you are ohming the plus of the plug you have disconncted through the coils of the other 3 injectors then through the ECM control ground. I would disconnect the other 3 injectors which will make the readings clearer. Then you should see infinite resistance on the plus side.
I think the ECM controls the neg or ground side of the injectors so as to make it harder to damage the ECM so that if by mistake you ground one of the ECM ground control wires so what? its already grounding it through the ECM.
please advice
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
Like I say before. just to make sure. like to know 2 things about this new test
1. do I umplug all the cable from ecm?
2. do I preform this test with the key to off
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
ok I did the new test. here are the conditions
ECM umplug
key to off position engine off
meter set to 20k ohms
meter negative prove to negativer battery pole
meter positive prove to inj wire ping 1, and ping 2
inj wire all umplug including cool start inj
i get the same reading in every injectors wire
here are the pics
[IMG]
[/IMG]
[IMG]
[/IMG]
[IMG]
[/IMG]
[IMG]
[/IMG]
ECM umplug
key to off position engine off
meter set to 20k ohms
meter negative prove to negativer battery pole
meter positive prove to inj wire ping 1, and ping 2
inj wire all umplug including cool start inj
i get the same reading in every injectors wire
here are the pics
[IMG]
[/IMG][IMG]
[/IMG][IMG]
[/IMG][IMG]
[/IMG]
Team Owner
Joined: Jan 2003
Posts: 20,315
Likes: 245
From: Summerland B.C. Canada
What does your meter show when probes are touching nothing ?
One of your pics looks like your meter's infinite signs. (no continuity)
You really need to see what wire is giving what reading.
One of your pics looks like your meter's infinite signs. (no continuity)
You really need to see what wire is giving what reading.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
ok I will have to go back to the car and se.
but the first picture show prove on the first ping on same plug wire. the next picture show prove in second ping in same plug wire.
I did test all the injector and I get the same reading.
i will go down and check what riding black prove to batery negative red prove to nothing.
i be back
but the first picture show prove on the first ping on same plug wire. the next picture show prove in second ping in same plug wire.
I did test all the injector and I get the same reading.
i will go down and check what riding black prove to batery negative red prove to nothing.
i be back
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
ok just test again.
meter set to ohms
black probe on meter to negative battery
the red probe to nothing
i get same exact reading show on picture infinity
i guest the ground side of wire is giving infinity sign. why. dont know you tell me.
Iam getting lost here with all this test. dont really know what all this meand.
i have done a lot of test can some one figura out what is going on.
meter set to ohms
black probe on meter to negative battery
the red probe to nothing
i get same exact reading show on picture infinity
i guest the ground side of wire is giving infinity sign. why. dont know you tell me.
Iam getting lost here with all this test. dont really know what all this meand.
i have done a lot of test can some one figura out what is going on.
Last edited by hitmanpty; Jul 16, 2012 at 11:53 PM.