D40 2.5D Auto (Spanish) Limp mode and more...

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bods

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I did have a quick re read of the thread and can't recall whether you've replaced the fuel filter since you purchased the vehicle?

If you're getting a code to say large fuel leak, the computer must be seeing a low rail pressure or it can't maintain pressure. On your obd scanner, can you see what the fuel rail pressure is? If you have logged this, it may show a major drop in rail pressure either from a faulty rail pressure relief valve or could be a blocked fuel filter too.
 

patchyfog

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I did have a quick re read of the thread and can't recall whether you've replaced the fuel filter since you purchased the vehicle?

If you're getting a code to say large fuel leak, the computer must be seeing a low rail pressure or it can't maintain pressure. On your obd scanner, can you see what the fuel rail pressure is? If you have logged this, it may show a major drop in rail pressure either from a faulty rail pressure relief valve or could be a blocked fuel filter too.
No, I haven't replaced the fuel filter since buying it - is there a recommended brand or can I just head to Repco/Supercheap/Cheapa and pick up the one they stock?

I've had a look at the log but it's all foreign to me. According to the .csv file, at idle (800ish RPM) fuel rail pressure seems to sit at around 4200-4600. Then, presumably when I shift it into gear, it spikes then drops and then the engine cuts (0RPM).

What's dropping first though - revs or fuel rail pressure?
 

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bods

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If you're not sure how old it is, or would be worth replacing it. I have been using ryco filters on my d22 since the warranty finished 7 years ago without issue. Just make sure you lubricate the seals with diesel or rubber grease before fitting and don't over tighten the filter and you won't have issues with air leaking around the seal.

Rail pressure looks OK, but I mean more when it throws the fuel leak code, would be interesting to see what it does then.
 

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If you're not sure how old it is, or would be worth replacing it. I have been using ryco filters on my d22 since the warranty finished 7 years ago without issue. Just make sure you lubricate the seals with diesel or rubber grease before fitting and don't over tighten the filter and you won't have issues with air leaking around the seal.

Rail pressure looks OK, but I mean more when it throws the fuel leak code, would be interesting to see what it does then.
Okay, I'll pick one up tomorrow. As for the pressure when it threw the code, it'll be on the same log. I've added a screenshot (marked) roughly where I believe the code popped up prior to me pulling over and wiping it.
 

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bods

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Looking at that sheet, the bit between the top 2 arrows, where the rail pressure goes from around 5300 to 8900 and back to 4900 I'd say is where it's thrown the light. Rpm and load haven't changed, so that seems a bit weird. Could be a sticky relief valve maybe, or sticky SCV. Have you run any of that liquimoly diesel purge through it? There's a thread on here that has been posted in again recently, might be in the d22 section, but that would be worth doing too just to make sure the rail, injectors and SCV are nice and clean.


http://www.navara.asia/showthread.php?t=27063
 

patchyfog

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Looking at that sheet, the bit between the top 2 arrows, where the rail pressure goes from around 5300 to 8900 and back to 4900 I'd say is where it's thrown the light. Rpm and load haven't changed, so that seems a bit weird. Could be a sticky relief valve maybe, or sticky SCV. Have you run any of that liquimoly diesel purge through it? There's a thread on here that has been posted in again recently, might be in the d22 section, but that would be worth doing too just to make sure the rail, injectors and SCV are nice and clean.


http://www.navara.asia/showthread.php?t=27063
Thanks @bods, I'll try to pick up a fuel filter today. I ran a bottle of Nulon Diesel Fuel System Extreme Clean through about half a tank ago - do you reckon I should put the Liquimoly Diesel Purge through too? If so, I'll pick one up when I get out to the shop as I'll have to fill at some point in the next week.
If the fuel filter change doesn't help I'll swap out the SCV as well.
 

bods

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I'd do fuel filter anyway, but I would try running a can of that diesel purge through before splashing out on a new SCV. Usually when they play up the motor will hunt around and stall on a cold start, but they can cause other issues. The purge will clean that too as it gets fed straight into the high pressure pump.
 

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I'm wondering why (second spreadsheet, line 279) your engine dropped to 250rpm with zero load, then returned to normal-ish idle with a higher air flow through the MAFS, which didn't change substantially for the light (4.7%) throttle blip at line 284.

I don't think the readings are 100% accurate, the fuel rail pressure around this time isn't fluctuating yet the engine RPM are (engine RPM is a direct reflection of FRP). This doesn't affect the average, so observations are still valid ...

Interesting to note at line 309 the engine RPM dropped to lower than the first time (211rpm) but this time the MAFS rate stayed much higher. Can you remember if the engine was actually suffering from extremely low revs at this point? It would appear that the data suggests the vehicle was in gear and being driven but at line 309 there's an engine load figure with the corresponding drop in RPM but no throttle application (throttle appears to have been released on line 308).

There's a good chance it's sucking air around the fuel filter. Cracked plumbing would allow this, offer erratic operation and throw stupid errors too because the ECU doesn't expect leaks like that. Can you pump the primer bulb 15-20 times? What happens?
 

Czechmate

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I had to replace all the fuel lines on my spainbuilt 07 STX pretty early on. They were all cracked and shitty by about 50,000 ks, vehicle 7-8 years old
The primer bulbs are known to crack and let air in too
 

patchyfog

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I'm wondering why (second spreadsheet, line 279) your engine dropped to 250rpm with zero load, then returned to normal-ish idle with a higher air flow through the MAFS, which didn't change substantially for the light (4.7%) throttle blip at line 284.

I don't think the readings are 100% accurate, the fuel rail pressure around this time isn't fluctuating yet the engine RPM are (engine RPM is a direct reflection of FRP). This doesn't affect the average, so observations are still valid ...

Interesting to note at line 309 the engine RPM dropped to lower than the first time (211rpm) but this time the MAFS rate stayed much higher. Can you remember if the engine was actually suffering from extremely low revs at this point? It would appear that the data suggests the vehicle was in gear and being driven but at line 309 there's an engine load figure with the corresponding drop in RPM but no throttle application (throttle appears to have been released on line 308).

There's a good chance it's sucking air around the fuel filter. Cracked plumbing would allow this, offer erratic operation and throw stupid errors too because the ECU doesn't expect leaks like that. Can you pump the primer bulb 15-20 times? What happens?
Hi, apologies for the delay.

You've lost me to be honest, Tony. I couldn't make nor tails of the data.
I pumped the primer after changing filters, it goes pretty hard after 15 pumps. Not solid but definitely harder than it started.

I ran a can of purge through it and swapped out the fuel filter and again had 2 weeks (200km) without issue. Then it went into limp mode again.
When I was changing the fuel filter I thought I'd have a quick look around the injectors - the 2nd from the cab had liquid around the top. I cleaned it off and put the cover back on. As I hadn't noticed it before but wasn't certain if I'd even checked, I continued carrying out intermittent checks of this area - it remained dry/clean. After getting back home from the drive that produced the limp, I decided to check it again. This time it's wet. I reckon this could be the issue - a stuffed injector seal?
On my old car, swapping out the injectors was a 10-minute job but that doesn't seem the case on these D40's - what's the deal? Can I simply just replace a single injector/seal or do I need the complete set-up of injectors and fuel line? How big a job are we talking?

Thanks
 
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patchyfog

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I had to replace all the fuel lines on my spainbuilt 07 STX pretty early on. They were all cracked and shitty by about 50,000 ks, vehicle 7-8 years old
The primer bulbs are known to crack and let air in too
The lines and primer bulb seem okay, at least to my untrained/novice eye. I may have to bite the bullet and take it to a mechanic...cut to hours trawling internet reviews of local mechanics!
 

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