2008 Patrol Diesel Pump not priming

[poddy]

It's a 2008 3.0 CRD

When starting the car, I turn the key, wait for the glow plug light to go out, then turn it all the way to crank. The engine turns over for a bit (4-5 seconds) and then it starts. It's a very lazy start, but it does start.

As opposed to what it should do - start right up - no excuses.

My assumption is that the diesel pump isn't priming prior to start, so it takes a few turns of the engine to get the fuel pump to build up enough pressure to ignite - but the fuel pump works, because once the car starts, it runs fine.

I am looking for pointers to what I should not miss, perhaps there is something obvious I am missing. Any info is greatly appreciated.

EDIT:
- when I prime the fuel with the hand pump just above the fuel filter, it gets hard on the third/fourth squeeze. If I leave it then, and don't start the engine, it goes soft again. And then, if I start pumping again, it doesn't get hard anymore, no matter how much I pump.
- I replaced all glow plugs, and tested voltage to the glow plug rail, which appears to be working fine. New glow plugs didn'tmake any difference.
- I ordered the replacement fuel pressure relief valve and will post an update once that is changed. (That was it, see below. )
- I have a injector leak back test scheduled for the weekend. - didn't end up doing this.

RESOLUTION: Fuel Pressure Relief Valve - replacing this $85 part resolved my long crank before start.

[PeeBee]

Check glow plugs, sounds more like that than fuel priming to me. The fuel will ignite in the cylinder based on compression and droplet size, when you say fuel pump are you referring to a lift pump or the injection pump? The lift pump is fitted between the fuel tank and the injector pump to provide a positive pressure to the injection pump inlet. is your vehicle a common rail diesel?

[Fireblade]

id be thinking glow plug relay (near the drivers right knee abour the fuse box)
or fuel pressure relief valve it might not be close allowing to build pressure, how does it start if you have it running then turn it off and then 10 seconds later start it back up? does it take awhile to start or does it go good?

check oul my thread about testint and replacing the valve
http://www.nissanpatrol.com.au/forums/showthread.php?43966-Zd30-crd-rail-relief-valve-test-and-replacment

[the evil twin]

Agree with the other guys... unlikely to be the pump on a CRD, possible but unlikely.

Check the glow plugs and operation first then move onto relief valve etc

[poddy]

I pulled the glow plugs out today and measuerd their resistance.
1 has 10 mega ohm resistance, 2 has 0.8 ohm, 3 has 1 ohm and 4 I wasn't able to remove. 82493
I also found a 10A fuse missing, the plastic cover just read "Glow"; It was in one of the fuse boxes in the engine bay. I re-installed the fuse - it didn't blow since.

I didn't check the relay. I've been trying to look up how to check a relay, but I am still a bit unclear - how do you guys check the relay?

Overall, my long crank before engine fires up remains unresolved. But I did order a set of new glow plugs NGK Y538J.

[poddy]

are you referring to a lift pump or the injection pump? The lift pump is fitted between the fuel tank and the injector pump to provide a positive pressure to the injection pump inlet. is your vehicle a common rail diesel?

Thank you, I found this very educative. And yes it is common rail. I went back and edited my original post after your query.

[poddy]

id be thinking glow plug relay (near the drivers right knee abour the fuse box)
or fuel pressure relief valve it might not be close allowing to build pressure, how does it start if you have it running then turn it off and then 10 seconds later start it back up? does it take awhile to start or does it go good?

check oul my thread about testint and replacing the valve
http://www.nissanpatrol.com.au/forums/showthread.php?43966-Zd30-crd-rail-relief-valve-test-and-replacment

Thank you this is very informative. Actually, cranking within 10seconds of shutting down a warmed up engine takes far less time, about 3 seconds. But it still isn't starting as it should. There is definitely a problem. But yes, when the engine is warmed up, I shut it, and then start it up, it does take considerably less time.

[poddy]

Agree with the other guys... unlikely to be the pump on a CRD, possible but unlikely.

Check the glow plugs and operation first then move onto relief valve etc

Already found 1 plug that is cactus. 2 are ok and 1 is unknown. Di CRD diesel pumps hace a rep of being solid? (Yep, I'm new here)

[poddy]

This is the one with a redistance of 10.52 mega ohm.
82495

[Bidja]

Question is at warm start up, does it stiil need to crank for several seconds before she starts up.

Understand that CRD will not start until all injectors obtain a even fuel pressure of approx 140MPa (20,000psi). This is why it can take several seconds of cranking to fire up because all have to come up to pressure. Need for an SME to conduct a return fuel leaking test.

May need to consider this.

[poddy]

Question is at warm start up, does it stiil need to crank for several seconds before she starts up.

Yes. Not as long as cold start, but yes, it takes about 3 seconds crank to start.



Understand that CRD will not start until all injectors obtain a even fuel pressure of approx 140MPa (20,000psi).

How does the engine know what the pressure in different cylinders is? What is this witchcraft?



Need for an SME to conduct a return fuel leaking test.

Sorry what is this SME?




May need to consider this.
I will thank you.

[Bidja]

poddy All good mate, SME is a Subject Matter Expert (eg: workshop that do Diesel fuel injector service / rebuild / repair and that have the tools and test equipment to check the injector serviceability.

Ring around local area, not sure where you are as someone around the forum may recommend w/shop.

Look not sure on injector sensors, but imagine a sensor would send signal back to ECU at time when same pressures are achieved in all injectors and initiate start. Others with more smarts may add.

For Info: My 08 CRD injectors were checked out 12 months back (originals_160,000ks), when fuel pump was replaced and all were within spec and she starts straight away always.

Have read that acceptance criteria is:
All 4 injectors _The maximum permissible return volume is 3 times as large as the lowest measured
Return volume.

This seems a lot but this is in accordance with Bosh documentation.

[pollenface]

It sounds like a candidate for an injector leak test, one of the injectors might be leaking excess fuel pressure via the fuel return line.

An injector is about $400 on it's own. A mechanic will usually advise/recommend that you have the whole set replaced.

[Fireblade]

has the fuel pressure relief valve on the rail been tested?
i linked a test method for you
note: you cant buy the valve from nissan they want to sell a complete rail you'd have to buy a bocsh on part number 1110010018
it could be an injector but check the fuel pressure relief valve first and then go to the injectors.
there is also a valve on the injector pump that is common to fail on common rail vehicles but seams to be very rare on zd30 crd patrols but to test that you'd need a computer to monitor the sensors to determine if its out of specifications

[Bidja]

Unless U already have a scan tool (to read trouble/fault codes), could be a good idea to buy one.

Many available, UltraGauge EMPlus is the one I use and is not too bad (OBD11 compatible). Apps out there as well.

http://ultra-gauge.com/ultragauge/ultragauge_wired.htm

[pollenface]

it could be an injector but check the fuel pressure relief valve first and then go to the injectors.

On the contrary, an injector leak test is fairly simple to perform, I would suggest doing that first before moving to the fprv.

[Fireblade]

to me they are both easy and simple tests, but from experience i feel its going to be the fprv. i may be wrong. leak back test is a good thing to be done anyway, cant loose by doing it.

[poddy]

thanks everyone, I've got the glow plugs on the way, will start with that; Like I mentioned earlier, I already found 1 is cactus (10.52Mohm); I've got a set coming in today, so I will swap them out - move on from there.

[poddy]

Just out of curiosity, when I was pulling the plugs out on the weekend, to check them, they were screwed in pretty loose. I mean, it took no effort to undo them from the block.

The manual says they should be tightened to 20nm, but when I last pulled them,they came out really easy.


I don't know what to make of it. Any thoughts?

[poddy]

Unless U already have a scan tool (to read trouble/fault codes), could be a good idea to buy one.

Many available, UltraGauge EMPlus is the one I use...



Looks interesting. Do you know if it can read the air intake pressure?

[poddy]

has the fuel pressure relief valve on the rail been tested?
i linked a test method for you...

Yes you did, and thank you for that Mr. Fireblade. I'm just slow with execution. Only just got the plugs delivered today, didn't get around to swap them yet. Then I move on. I appreciate the help with this.

[Bidja]

poddy UltraGauge EMPlus _ IMO is good kit and yes does display boost pressure (absolute and gauged) from MAP sensor (cold side cooler) via ECU. Example of one page that I use. Price has dropped from $149 couple of yrs ago.

[Bidja]

Just out of curiosity, when I was pulling the plugs out on the weekend, to check them, they were screwed in pretty loose. I mean, it took no effort to undo them from the block.

The manual says they should be tightened to 20nm, but when I last pulled them,they came out really easy.


I don't know what to make of it. Any thoughts?

Guess made it easy to remove them. Just use one of your old glow plugs and run then in and out (bit of lube/oil, diesel or something) to make sure the threads are clean of any residue.

[poddy]

Check glow plugs, sounds more like that than fuel priming to me. The fuel will ignite in the cylinder based on compression and droplet size... It's not the glow plugs; I've swapped the set and nothing changed. Not a damn thing. But yea, I see where you were coming from. 2 were no good anyway, sothat would have to be done anyway. Thank you :)


id be thinking glow plug relay (near the drivers right knee abour the fuse box)
K, I don't think it will be the relay; I've had the multimeter hooked between battery (-) terminal and a tip of one of the NEW glow plugs, and it behaved like they describe in the manual that it should. It had around 11V when priming, opr when the glow plug little light on the dash was on. And it would return to 0V when the little dash light went out. So I made an assumption this behaviour is correct. Please do correct me if I am missing something. Many thanks.



or fuel pressure relief valve it might not be close allowing to build pressure, how does it start if you have it running then turn it off and then 10 seconds later start it back up? does it take awhile to start or does it go good?

check oul my thread about testint and replacing the valve
http://www.nissanpatrol.com.au/forums/showthread.php?43966-Zd30-crd-rail-relief-valve-test-and-replacment
Yep, this is the next patient for Dr. Poddy. Thank you so much for that link; I'll post back when done.


Agree with the other guys... unlikely to be the pump on a CRD, possible but unlikely.
Check the glow plugs and operation first then move onto relief valve etc
On it. :)

I'll move onto the fprv tomorrow and then see how that goes. I'll keep you posted. Thanks everyone.

[pollenface]

That's a good looking unit!

[Bidja]

That's a good looking unit!

who the gauge?

[poddy]

poddy UltraGauge EMPlus _ IMO is good kit and yes does display boost pressure (absolute and gauged) from MAP sensor (cold side cooler) via ECU. Example of one page that I use. Price has dropped from $149 couple of yrs ago.

Hey mate, did you order this from the States? And was it just straight plug in, no tinkering required?

[Bidja]

poddy the UltraGauge (EMPlus) that I procured does not support air intake temp, not all gauges / parameters can be accessed. Access @ user level (us) is limited by what access Nissan allows. Not sure if the UltraGauge MX gauge variant provides access to the parameter. Would be interested in reading this as well and also AFRs_maybe someone else might chime in with more insight on a suitable gauge or a smart phone App that can support air intake temp.

I bought the gauge direct from the US via their web page (linked provided earlier). Yes the gauge is pretty well a plug and play, you just need to select the gauges that you want to view on each of the 5 pages (total of up to 8 gauges per page). One thing to note is that, if U wish to view torque (N-m), the load gauge has to follow (next) to the torque gauge (refer my earlier post (shows torque gauge and then eng load). You have to know the max torque produced from your eng (eg: from dyno), key that in and torque then is calculated / displayed as a factor associated against the eng load.

Edit_thought you asked if the UltraGauge could read intake air temp_now cannot see your post, Never mind responded anyway. Post #20 refers found it_all good.

[poddy]

thanks mate.

[poddy]

And also big thanks to everyone that chipped in this thread. Problem sorted. I re-edited the first post with the resolution. :clapping: