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2012 Nissan Juke - No Injector Pulse - HELP

posted Jun 12, 2016 18:57:23 by HolmerArgent
This car, came from another shop, i am told that ecm has being replaced, due to no injector pulse, car cranks alright but no injector pulse, when fuel is send into the inlet, it start alright till the fuel finished then it is off, this means the injectors are not opening, please i seek for advice what might be blocking the earth.

N.B: No fault code at all
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16 replies
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cheryl hartkorn said Jun 12, 2016 20:50:37
the ecm been replaced? or you mean its going to be replaced? because if it has been already replaced the immobilizer will need re programmed. also do you have power on one of the wires to the injectors? just because it starts on alternative fuel doesn't mean its an injector problem besides there would most likely be codes stored. id be going more after the fuel pump first
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HolmerArgent said Jun 12, 2016 21:18:58
yes key has being programmed, to the new ecm.

No fault code display...
no matter how long you crank or turn the key on, scan tool communicate rightly
[Last edited Jun 12, 2016 21:30:34]
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Tyler said Jun 12, 2016 21:46:46
I'm kinda thinking along the same lines at Cheryl, are you sure that you're dealing with a lack of injection pulse, as opposed to a lack of fuel pressure?

Beyond that, the first thing that comes to my mind is a cam/crank sync issue. If there's no scan data PIDs associated with timing, then the next step would be to scope both signals and compare to a known good.
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HolmerArgent said Jun 12, 2016 22:21:59
Well, do not have scope apparently, yet to get one even though i have no knowledge in it but i am willing to learn something new.

but is there a way to check with DMM,

if cam and crank error why start with start fluid till the fuel finish from the inlet, this is just a question sir
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Tyler said Jun 12, 2016 22:59:25
if cam and crank error why start with start fluid till the fuel finish from the inlet, this is just a question sir


Ah yeah, that's my fault, didn't explain my reasoning very well! I've encountered cam/crank sync issues where the PCM is able figure out spark timing, but can't figure out injection pulse sequencing. So you end up with spark without injection pulse, or very intermittent injection pulse.

Well, do not have scope apparently, yet to get one even though i have no knowledge in it but i am willing to learn something new.


I understand, no worries.

but is there a way to check with DMM


Not the cam/crank relationship, unfortunately. You could check the sensor wiring and power/ground, but not the signal waveforms themselves. Though, we're still not sure about the whole cam/crank thing, so that may not be a big deal.

Like Cheryl was saying, you're probably better off verifying fuel pressure and power/control at the injectors before going deeper.
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HolmerArgent said Jun 12, 2016 23:11:13
Alright buddies, but here lies the came the ecm has good earth, and good power feeds, the injector one side has IG current when key is turn on. fuel pressure is 56 psi during cranking.

question: is it rare that a chain timing can jump, if yes then why no code on cam sensor?
[Last edited Jun 12, 2016 23:22:16]
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Tyler said Jun 13, 2016 00:10:46
Alright buddies, but here lies the came the ecm has good earth, and good power feeds, the injector one side has IG current when key is turn on. fuel pressure is 56 psi during cranking.


Nice, great to hear sir! That helps to answer a lot of questions about the PCM and the rest of the vehicle.

question: is it rare that a chain timing can jump, if yes then why no code on cam sensor?


Chains have been known to jump, depending on the engine and how it's been maintained. Why no cam sensor or cam/crank correlation code is a fair question, which I guess would depend on the code set criteria. Noah (another forum member) posted recently about an Acura with a jumped chain, not starting, with no codes.

I have heard from other techs that you can try unplugging the cam sensor and retry starting. If you now get it to start and run after a long crank time, then you're likely looking for a timing issue (or at the very least, a timing input issue).
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Noah said Jun 13, 2016 02:34:03
Noah (another forum member) posted recently about an Acura with a jumped chain, not starting, with no codes.
Sorry bud, still won't link to the forum.
If I remember correctly, that car was even managing to fire the coils pretty close to TDC, only was I able to nail it down to jumped timing when checking the Cam and Crank sensor signals against a known good car.
That was the justification we needed to pull the timing cover and check the marks. (Which really was simple, and wouldn't have been the wrong thing to do had I not had a scope.)
Massachusetts, USA
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IvanKibuka-Kiguli said Jun 13, 2016 08:14:14
Holmer, did you say the engine runs for a short time and then stops? If so, have you checked for fault codes in the NATs system? This could be an immobiliser issue...
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Noah said Jun 13, 2016 11:24:09
That's a very good point Ivan.
There should be a PID in the anti theft module thread should display something like " Fuel enable/disable".
Massachusetts, USA
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HolmerArgent said Jun 13, 2016 13:10:19
Great input by all you commented on my issue, i am very grateful... blessed is the man who help his fellow, for theirs is reward await for them...

Now talking about immobilizer issue, while the key light does not stay on steady nor flashing while cranking, or while thrown fuel into the inlet and it started for a while till the fuel get finished, but i will take a look at the PID info and see the enable/disable thing for the mean time... Noah and Ivan..

Tyler: do you want to say that, the crank sensor alone can let the car start on start fluid, while the cam has being unplugged, please comment on this well, is this criteria to all cars, if i may ask?
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George said Jun 13, 2016 14:58:10
Tyler: do you want to say that, the crank sensor alone can let the car start on start fluid, while the cam has being unplugged, please comment on this well, is this criteria to all cars, if i may ask?

If the ckp has a distinctive (sync) notch, it most likely will, because the ecm knows when "a" cylinder is in TDC.

fuel pressure is 56 psi during cranking

If you open your ignition to the on position you will hear a prime for around one second and then it shuts off, if you crank the vehicle does it(the fuel pump) keep running? if so, your inputs are likely to be ok.
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HolmerArgent said Jun 13, 2016 22:57:17
hi buddy, back from test, the immo status in the live data stream is ENABLED during cranking time, and the fuel pump really is closed during cranking as well, this means it keep running it does not disconnect..

so what else could be causing the injectors not to send the triggering signal, this is my headache now
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George said Jun 14, 2016 21:31:53
what else could be causing the injectors not to send the triggering signal, this is my headache now

I think it's time for scope patterns of the ckp-cmp.
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AndresRohena said Jun 15, 2016 04:54:51
In my opinion if you have power supply to the inyectors with out any injector pulse there's a few thing that come to my mind first if you have those 56 psi forget about the pump now nissan has a very common problems with the timing chain if the chain jumps it wont start or starts for few second and then shut down that's when the crank/cam synchro comes to the place a lot of nissan 2.5 motor do that, in that case they send i think is a p0340 cam sensor malfuction. Some one mention about the anti thef system remember when mitsubishi use to have problems with the immobilizer they do this same case!!!
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