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NA Auto not starting


tayr
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Hi Guys,

Looking for some advice, I’ve received some help already but looking for some more opinions on what to check next.

the car is an NA Auto and ran fine. It idled high but that was it. Rolled it into the workshop, removed the carpet for dying and thought nothing of it. Went to start it after a couple weeks and nothing. It cranks but won’t fire.

as far as I know the car de-mobilises as the lights come on on the dash once the unlock button pressed again.

 

here is what I have investigated so far - does anyone have any ideas where to go next?

- Checked EFI Fuses

- Checked Fuel pump ecu

 - Checked fuel pump

- checked spark plugs, they are fine and not wet

- Checked igniter

- checked coil lead

- check diagnostic and B+ getting 12v

- bridged B and P and can hear fuel pump running with ignition on

- loosened off fuel filter pipe engine side and fuel is getting through from back and through the filter

- opened up ECU and everything ok

- checked all fuses

- checked earth on both kick panel sides

- checked earth to engine

- checked earth to igniter

- changed battery

- changed fuel

- used carb cleaner to start, fires for 1 second then cuts out 

- the loom coming into the car and ecu look in great condition 

So it has Air and spark but I have a feeling the fuel isn’t getting through the final bit, can anyone tell me how I can check or where to check? Ie what to loosen off etc to be able to check? Likewise if anyone can suggest anything else that’d be great !

only other thought is maybe the immobiliser on the car has a fuel shut off? But no idea what brand it is or where to find / access it to disable it or bypass it. I found a black box about 4” x 6” behind the dash but no idea what it is and can’t really unplug it

 

 

 

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Have you checked it's sparking at the actual plug?

 

i.e. taken a plug out, plugged it back onto the lead, grounded it and span her over.

 

Much more basic but I had a similar thing with an MG years ago. Couldn't find the issue but it turned out to be the Rotor arm had a crack in the conductive section.

Edited by TheTurtleshead (see edit history)
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Posted (edited)
52 minutes ago, TheTurtleshead said:

Have you checked it's sparking at the actual plug?

 

i.e. taken a plug out, plugged it back onto the lead, grounded it and span her over.

 

Much more basic but I had a similar thing with an MG years ago. Couldn't find the issue but it turned out to be the Rotor arm had a crack in the conductive section.

Hi James

 

Yeh I did do that and it was sparking so I think that’s ok..

do you know if some Immobilisers control fuel?? Scratching my head as to why it suddenly just stopped firing

 

will also check fuel rail and fuel pressure sensor. Wonder if it’s worth looking at throttle position sensor and idle control valve but think I’m clutching at straws 

Edited by tayr (see edit history)
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Ok so, definitely spark, I checked and the plug sparks every couple of seconds or so. They are still dry though. There is fuel getting into the FPR but not sure if it’s coming out into the rail so I guess rail next to check? 

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If its fuel issue, then you should be able to spray some easy start down the intake whilst cranking and it should fire for a few seconds. If you can get that far, then defo either ECU control has failed, wiring problem (check you have 12v on injector connectors) or mechanical issue with fueling. 

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56 minutes ago, Mike2JZ said:

If its fuel issue, then you should be able to spray some easy start down the intake whilst cranking and it should fire for a few seconds. If you can get that far, then defo either ECU control has failed, wiring problem (check you have 12v on injector connectors) or mechanical issue with fueling. 

Thanks Mike, I did use easy start and it started once for 5 seconds then wouldn’t start again no matter how much i sprayed it. I wonder if the flap is opening or not.. I’ll check that tomorrow. I’ll check 12v on the injector connectors too. Good shout! In the meantime I’ll try find another auto ecu to try, I did open both sides and it looked spotless but worth a try 

Edited by tayr (see edit history)
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You can hook up a light to the injector to make sure its firing while cranking. Keep in mind after the ECU receives no confirmation of ignition fired (IGF signal) after 2s it cuts fuel to avoid flooding the cylinder, so your light will stop blinking if your issue is spark or ignitor related.

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  • 4 weeks later...

Ok so I still need to hook up a light to the injectors but In the meantime I checked the voltages. All showing as circa 10volts when ignition on.

I did however notice that fuel is going into the fpr (I think that’s what that is?) but not coming out the other side. When I spray easy start up the tube it starts for half a second then cuts out. Could this be the issue?

   

 

Edited by tayr (see edit history)
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That hose you removed from fuel pressure regulator is just the vacuum pipe to manifold for it I think buddy like Noz says try wiring pump direct or crack hose at fuel banjo near inlet or at fuel filter but fuel will come out at pressure if pump kicks in which isn’t exactly safe 

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The  pump is controlled by fuel pump Ecu drawing power from efi relay#2 from the fuses marked efi fuse#2 so if these are all okay and the pump ecu is working wire pump direct to power just to see if it kicks in  

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i had a little time this morning and un-did the banjo at the downpipe side of the fuel filter, turned the car over and it p*ssed out like a supersoaker so it's definitely getting through. 

What's next to check?

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11 minutes ago, Noz said:

Regulator.

You know I can't remember if I have my old rail. I should go and check that for you actually. I uprated all mine so i might have a regulator I can post to you.

Have you taken lid off ecu. To see if caps and juicy

Isn't the bit in the video above the regulator? or is that something else? when i undo the nut on the right hand side fuel comes out of it, but not sure if it goes through it.

Took both lids off, the caps are as clean as a whistle

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1 hour ago, tayr said:

Isn't the bit in the video above the regulator? or is that something else? when i undo the nut on the right hand side fuel comes out of it, but not sure if it goes through it.

Took both lids off, the caps are as clean as a whistle

The bit? You've highlighted the regulator yes. The vacuum hose is just air, going to the intake. Banjo is the return fuel.

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3 minutes ago, Noz said:

The bit? You've highlighted the regulator yes. The vacuum hose is just air, going to the intake. Banjo is the return fuel.

going to see if i can test the pressure but need to find an adaptor

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You should have ordered that fuel pressure regulator I told you about with the dial instead of faffing about measuring how far the bloody fuel squirts out.

If you want to boost the car, just upgrade the fuel pressure regulator now, and then its ticked off the list and crossed off as a potential root cause.

Edited by Noz (see edit history)
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1 hour ago, Noz said:

You should have ordered that fuel pressure regulator I told you about with the dial instead of faffing about measuring how far the bloody fuel squirts out.

If you want to boost the car, just upgrade the fuel pressure regulator now, and then its ticked off the list and crossed off as a potential root cause.

wheres the fun in that?

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Took off the return line today, cranked it and pissed out everywhere so it’s definitely getting through.

 

the injectors are all also working when cranking as I can hear them clicking.

checked and change the 30A fuses again

Opened the ecu again to check it and still can’t see any leaking caps anywhere. But going to try and change it anyway see if that helps 

Edited by tayr (see edit history)
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  • 3 weeks later...

So - an update.

Swapped the ECU in case. No difference..

Checked the fuel all the way from the tank up to the rail and it's coming out and from the return at high pressure.

I did tap the injectors and now rather than just cranking, it does try to fire every 1-2 seconds but won't actually fire. Easy start has it firing for half a second.

That makes me think maybe the injectors are the fault. i do have spare so going to change them this weekend and clean plugs up at same time. 

 

Why is the GE such a pain in the backside to get to the plugs/injectors

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