D22 YD25 limp mode?

[samt9892]

Hi,

My 2013 D22 YD25 (244000kms) started having a rough idle a few days ago after start up. Hunting from its usual idling rpm of 750 up to almost 1000. Thought it was just the cold weather starting in WA.

Then today when driving to work I started to loose most of the power and my injectors became suspiciously quieter than usual (they are noisy normally when under load).

Turned on my bluetooth scan tool and noticed that the fuel rail pressure wasn't ever rising above 70000kPa on the live graphs.

Turning the car off and on again corrected this, but the next time I would have to idle in traffic for longer than about 30 seconds the same thing would happen.

After work my car immediately threw an engine code on startup:
- P0089 - Fuel Pressure regulator performance

Did some troubleshooting tonight including:
- clear hose from fuel filter line to injector pump - no air lock, system primes and holds pressure fine using the hand pump on the filter
- Loosened fuel cap - no sucking in of air and made no difference to performance
- checked the fuel pressure relief value on the back of the common rail - removed return hose and got her up to 4000rpm, no fuel leaking out so don't think that valve is bleeding pressure, I did find it weird that the hose from the valve was pressurised though and diesel would flow out when removed from the valve and the motor running (I thought that was just a return line for excess diesel / pressure ?)
- Last fill-up was from a large shell in central Perth, though I will top her up from elsewhere to dilute any bad fuel in the tank
- last fuel filter change was <5000km ago
- leaving batteries off tonight to reset the ECU

Went for another drive this evening and managed to replicate the same fault - again only starts after driving for a bit then idling for >30 seconds, after that engine load stays <33% and rail pressure <70000kPa always.

I have uploaded a picture of the log from the evening drive (OBD-II reader)
you can clearly see after I stop for the second time and idle for a while the fuel pressure / engine load refuses to go up despite me booting it.. (top graph is engine load %)

Anyone had anything similar happen with their D22? Reading that this is a pretty common thing with the D40s and the SCV is to blame?

Don't really have a mechanic I can trust in Perth and as a poor PhD student I'm hoping this isn't the injector pump $$

Any suggestions / advice much appreciated!

Cheers
Sam

 

[freerider170]

I'm new to Navara, so I can't help you sorry, but what software do you use? I'm using torque lite.
Thanks and hope you'll get her fix soon

 

[Old.Tony]

It could be the SCV. A bottle of injector cleaner might do the trick, and that would be my first go-to.

The one I use is this one (it's a little dearer than it used to be, but I guess bread is too!):

Liqui Moly Fuel System Cleaner/Conditioner 500mL

Liqui Moly Fuel System Cleaner/Conditioner 500mL

www.supercheapauto.com.au

 

[samt9892]

I'm new to Navara, so I can't help you sorry, but what software do you use? I'm using torque lite.
Thanks and hope you'll get her fix soon

I use 'Car Scanner Pro' with an OBD-AUS reader. Tried torque pro but couldn't get it to connect to my reader - suspect it was something to do with having 2 OBD apps installed at the same time.

Thanks Old Tony - I will try the fuel system cleaner and a top up at BP at the weekend and report back

 

[samt9892]

Filled up with BP ultimate and ran a bottle of that Liqui Moly Fuel system cleaner that @Old.Tony kindly linked.

Unfortunately the issue persisted over the weekend - I get maybe a maximum of 10 minutes use from the car before limp mode is entered and the fuel rail pressure is limited.

Just purchased a new SCV from Repco for $170 on sale, so will try that this week.
Found one video online about SCV replacement in the D22 2.5:

Has anyone done this job themselves? looks pretty easy just 2 hex bolts, though access isn't great, anyone has some tips on the process?

Cheers
Sam

 

[Old.Tony]

It's usually 2 torx bolts, so be careful there. That, and the electrical connector. Apply a little diesel to the thing before insertion.

I can't do my own any more, unless it's around a motorsport event when I'm taking enough antinflammatories to keep Uncle Arthur at bay, otherwise my hands just can't undo the electrical connection let alone manipulate the torx wrench.

 

[samt9892]

So I changed the SCV today,

Its was a pretty easy job - just remove the two fuel return lines that are in the way and make sure the rubber gasket is seated on the back of the fuel pump (rather than on the back of the SCV where it can move and pinch)

I started the car and the rough idle had gone, but the rail pressure was 90000Kpa which was way too high and the injectors were loud. Confused, I took the car for a short drive and it went back into limp mode and threw the same engine code.

I then did the pedal dance ecu reset as follows:
1. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly five times within 5 seconds.
3. Fully depress the accelerator pedal.
4. Fully release the accelerator pedal.
5. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MI starts blinking.
6. Fully release the accelerator pedal.
— ECM has entered to Diagnostic Test Mode II (Self-diagnostic results).
7. Switch Ignition off to exit

Restarted the car and rail pressure down to a stable 30000kpa and limp mode gone!

Will do a longer drive tomorrow but I'm pretty sure this is fixed

To anyone doing this in the future - remember to reset the ECU after an SCV change

Cheers
Sam

 

[gazza414]

Just following up...no problems since the SCV change