2008 D40 starts then stops 5secs later

[BenL]

Hi all,
Long time reader, first time to post. And I should thank you all for the help you've provided over the years.

My 2008 D40 has developed an issue that when at running temperature will start, run for 5secs then stop. This is a reliable 5 secs which makes me think it's an electrical or NATS issue. I have to sit and wait 10mins or so, then she starts first time. I don't get it.

I searched here and some have had issues with the fuel filter o-ring, but a) I've only recently replaced this and b) it would run longer than 5secs while the filter bowl empties.

In desperation I've replaced the key battery, but I know the chip doesn't need power to register.

Has anyone any clues where I could start looking?

 

[Old.Tony]

I wonder if the fuel pickup is blocked in the tank? If you rev the engine, does the 5 seconds reduce to something less? That would clearly place the problem with fuel delivery. Does it extend if the fuel cap is loosened?

I wonder if the SCV is dirty? It would be very difficult to get enough injector cleaner through if the car only runs for 5 seconds, so the SCV would have to come off. Wash in petrol, rinse in fresh diesel before reinstallation.

It could be the fuel primer. Have heard of a couple of those cracking and allowing air to leak in. When the pump starts sucking fuel, it will draw from whatever's easiest - and since fuel is MUCH denser than air, it will draw air from the leak first.

 

[BenL]

Confirm diesel

Hi again,

Thanks Tony, I'll investigate those areas first.

I should confirm to all that yes, it is diesel 2.5 Spanish build.

Tony, no the timing to shut down is the same if I rev it off the start.

I'll try the fuel cap to see if that makes a difference. I'm looking through the service manual now but can't see where the SCV is located. I'll keep looking but any guidance would be appreciated.

A sparky mate over the phone suggested I look at the lift pump, and fuel delivery also thinking that if the system isn't registering the right pressure, the ECU will shut it down. Sounds logical. Sounds like I've got to start pulling the fuel system apart.

There's a clue with the wait time though. Why does it start working after 10mins or so? Not 1 min, 2mins, 5 mins, but close enough to 10mins from the last start attempt. Every time. That's the bit that's confusing me at present. Alternatively, is there a relay that could stick, that unsticks after that amount of time? And this only happens when the engine is hot, and I've stopped for less that 5-10 mins (like a fuel stop). I'll keep you updated.

 

[Black_Outlaw]

Firstly, your SCV is located on the drivers side, at the rear of the pump.. its held on my 2 M10 Socket bolts...

Remove the eletrical contact, and then the 2 bolts.. and pull backwards.. it should remove easily.. Not which way you removed it..... Also, remove the positive battery lead.. This will effectively clear your idle learn and fuel pump settings..

Now rinse in petrol, making sure you move the "nose" part in and out, as that i where, if any, the dirt will be..

Now when it's dry and you're ready to refit, simply pump the fuel pump under the filter to get some diesel into the SCV.. Also, re-insert 180 DEGREE'S from the way you took it out (basically install it upside down)...

Bolt up, replace electrical connector, replace positive battery terminal and then pump the fuel bulb a few times until its firm.

Start car.. And test for fault..

 

[Old.Tony]

I'm trying to find info about the NATS and they're bloody closed-lipped about it. I guess they don't want outsiders figuring out how to steal the car.

The only thing I can offer is that if the NATS detects any problems, the security light (that normally flashes when the car is off) will light up when the ignition is turned on. As far as I can tell, you're not supposed to be able to start the car at all if the NATS detects that there's a problem with the key.

 

[kernels]

I read somewhere that the Thai built Navs have crank and cam sensors that check for cam chain wear and will shut the engine down a few seconds after starting if it detects excessive chain stretch. But the Spain ones didn't have this I believe.

Have you tried connecting a OBD reader to see if there are any logged fault codes ?

 

[BenL]

Tony, no security light when the ignition is on. I also considered that. But not ruling it out either.

Kernels, I haven't got a reader myself but hope to locate a mate who has one in the next day or so. I'll report back if anything is recorded, though no warning lights are coming up.

Black outlaw, I appreciate the pics. Looks like a bit of a twist to get it but I'd rather be doing it than paying a dealer.

This coming weekend I'll replace the fuel filter again this time with a genuine part, block the EGR and reset ECM/fuel pump. I'll clean out the SCV, though I'm not convinced it's this yet - if it were blocking up I'd expect to see the idle hunting.

I really appreciate your time guys. Thanks again.

 

[BenL]

update

Just a quick update, the problem seems to be resolved, though I'm still not confident I've nailed the issue.

I thought I'd leave the SCV cleaning to another week, as the idle has been stable as the day she was new, which I suspect wouldn't be the case if the SVC was sticking.

My main suspicions were a sticking EGR valve, or a clogged fuel filter which I wanted to test first before moving onto the SCV.

I blanked off the EGR valve as per advice on these forums and can very much recommend it. Easy and cheap job, and the car is nicer to drive. Spools a lot sooner so more power off the mark.

Fuel filter was changed too with a genuine Nissan filter just to be sure. And then I reset ECM/Fuel pump.

...and now it starts every time.

The filter itself didn't seem to have dirty fuel remaining in the bowl. The switch/plug at the base of the filter was a lot looser than the new one, which could be the fault, but if air were leaking in allowing fuel to return, I would have had issues any time I tried to start, not only when the engine's warm.

So my main suspicion is that the EGR valve was sticking open, and wouldn't close until 5 to 10 mins later allowing me to start the car again. Blanking it off has removed this issue all together.

If the issue resurfaces, I'll clean the SCV and report back.

Thanks again everyone.
-BenL

 

[kernels]

Nice one Yeah, that EGR block is a total no-brainer.

 

[mike1303]

I cleaned my scv then replaced it the next week. Found it did nothing to improve at all

 

[Black_Outlaw]

My idle would hunt first thing in the morning, and if left for a period of time, would almost come to a stall the hunt got that bad..

Cleaned SCV and idle stabled - but it started to return again a week later.. Purchased new SCV and car runs crisp and idles smooth again..

Blanking the EGR seems to be your fix.. how much CRUD was in there?

 

[steel d40]

Had the same issue and replaced the primer bulb. That sorted mine.