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GU ZD30 Di hesitation & starting issues


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I would not loosen injector line!

The only way to find out is connect clear hose from filter to pump and check for air in the system (bubles)

Also are you sure your glow plugs are up to a scratch or actually work. To me it looks more like glow plugs if it starts right away when warm.

How cold is in the morning?

The bolt on the ECM plug, mine has been broken for years, I broke it undoing it with just little ratchet. Plug is held in place by giant cable tie wrapped around the ECU.

Regards

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41 minutes ago, Rumcajs said:

I would not loosen injector line!

The only way to find out is connect clear hose from filter to pump and check for air in the system (bubles)

Also are you sure your glow plugs are up to a scratch or actually work. To me it looks more like glow plugs if it starts right away when warm.

How cold is in the morning?

The bolt on the ECM plug, mine has been broken for years, I broke it undoing it with just little ratchet. Plug is held in place by giant cable tie wrapped around the ECU.

Regards

If I connect the clear hose and I see bubbles, how would I remove them from the system? I have tried priming while cranking and also primed when the engine started for about 2 minutes, think I did 200 pumps in that time.

Ah okay how would I check the glow plugs? I did spray the connector to them and was alot of dust and dry mud inside and the metal line that connects them all doesn't look great either! If I am to replace them do I need the ceramic tip ones? I want to do the timer mod on them also and use the metal ones if they hold up better/longer.

It's usually around 6-7°c on average most mornings.

Ah all good I used a big zip tie and tied it around nice and tight right in the middle where the screw used to be.

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With such temps in the morning I'm sure glow plugs are not up to the job anymore.... 

You will need to check resistance accross the positive terminal of the glow plugs and its body (or nearest ground). So you will have to remove intercooler and buzz bar. Glow_plugs_checking.jpg.15c8bbb1c3c78732aeeb412277d2b6f0.jpg

If you find that values are out that means removing them and inspect visually if the tips are still there.

Metal glow plugs are cheaper but wear out very quickly about 20k so the timer mod is absolutely essential indeed it is in any case. The stupidity of glowing for 5 mins.

Ceramic tips glow plugs last longer 100k but are way more expensive but with the timer mod as well you'll probably don't need to replace the next ten years. Nissan also wnat you to replace them with right ones too. I can confirm that the ones with blue mark are ceramic type. See bellow.

Glow_plugs_identification.jpg.f7a4bbd7c81bbdea5c186310a424352d.jpg

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23 minutes ago, Rumcajs said:

With such temps in the morning I'm sure glow plugs are not up to the job anymore.... 

You will need to check resistance accross the positive terminal of the glow plugs and its body (or nearest ground). So you will have to remove intercooler and buzz bar. Glow_plugs_checking.jpg.15c8bbb1c3c78732aeeb412277d2b6f0.jpg

If you find that values are out that means removing them and inspect visually if the tips are still there.

Metal glow plugs are cheaper but wear out very quickly about 20k so the timer mod is absolutely essential indeed it is in any case. The stupidity of glowing for 5 mins.

Ceramic tips glow plugs last longer 100k but are way more expensive but with the timer mod as well you'll probably don't need to replace the next ten years. Nissan also wnat you to replace them with right ones too. I can confirm that the ones with blue mark are ceramic type. See bellow.

Glow_plugs_identification.jpg.f7a4bbd7c81bbdea5c186310a424352d.jpg

Thankyou very much for your helpful information! I will check them tomorrow and look at doing the timer mod with ceramic glow plugs to prolong the life and not have to worry for a very long time 😁

So how would I go about bleeding the air properly from the fuel system? Have I been doing it right in priming while cranking and while the engine idles? I don't see a bleed screw or anything to bleed the air to the upmost part of it's path so I'm not sure how to do it correctly if you can help with that thankyou.

Feel like I'm slowly getting to the bottom of things by process of elimination, it's just the hard starting that's my only issue at the moment as well as some air in the fuel which is an educated guess so far but I want to bleed the system to make sure of it!

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8 hours ago, bistratoaie said:

So I just got my ECUTalk cable today and these are my readings on first start up of the day 26°c outside.

Do these readings look okay so far @Rumcajs? Am yet to diagnose my glow plugs.

20201102_123036.jpg

20201102_124413.jpg

Hello,

Finally you're cooking with gas.....

The most important gauges are:

RPM, Water temp, Battery V, Throttle V or %, Injection Timing % (duty cycle),  Air flow, Barometer, Fuel Temp, VNT Turbo %.

 MAF Voltage seems a little higher for idle....

If Injection Timing % is bellow 40% you have air in the system or problem with fuel. Normal operation around 50-70%. So in yours, barely reaching 41% at idle  yes you have problem with fuel delivery.  add external lift pump and you will find the leak quickly.

However you MUST carry out SPILL/OVERFLOW LINE modification otherwise you will pump fuel backward in to the injectors and cause major failure.

In this imbecilic design of the injection pump fuel is used to cool, lubricate as well so not enough or starvation will destroy the injection pump very quickly. Fuel starvation is the most common reason for the pump failures. One way to mitigate is to add external lift pump like carter 4601 to Walbro 13-2 ....The arseholes from Bosch who ripped this design from the UK have caused so much heartache and financial damage to the owners of those cars with that abomination VP44 radial injection pump. But generated a handsome profit for the manufacturers! Just search VP44 failures on Internet!

Fuel temp is also very important keep in mind it depends a lot on ambient temp but continuosly above 60-70 C will spell trouble for the pump.

Yours doesn't show turbo boost (absolute pressure), mine does so yours is series 3 and less.

Air in the fuel is very difficult to diagnose, one thing to remember is that if the fuel pipe from the tank is compromised then air will get in.

Another source of air getting in is primer on the top of the fuel filter.

I'd also check hoses on the fuel tank, under the cargo space is a cover to reach to the pick up. 

One resort is to use a jerry can and rig up temporary fuel delivery to by pass pipes and tank to see if the air is sucked in at filter housing.

Or if you have access to air compressor and regulator  trick is to remove fuel line at the pump, block it with a bolt or something then remove fuel line at the tank pickup and pressurize the fuel line and find where air is leaking if any,  or get a spare tank cap and drilled and fit airline fitting to it. (that's how it is done by some workshop or some manufacturers.  Remember low pressure only (max 100 kpa ).

I'd avoid driving the car until you identify why Inj Timng C/V % is low. If you wish, warm up the engine and go for test run around the block and check what you get at WOT (wide open throttle) Anything bellow 30 is  massive trouble! You can log the data from those gauges in ECU Talk in to CSV sheet and open it in Spreadsheet app of your choice or just text editor.  Set up log for the Inj Timing C.V %, RPM and throtle % so you can collate the data and see instead of starring in the laptop screen while you drive.

Regards

Edited by Rumcajs
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Ah yes, the higher reading is due to a 3" straight through exhaust and the EGR blocked off which I read on another thread that 2.15v is okay on idle however; I did notice it linearly got to 4v around 3000-3500rpm while revving and watching the voltage.

I do believe I have air in the system from the "3rd small o-ring" at the fuel filter primer because the fuel filter was replaced last month and I think they may have lost or forgotten that o-ring as the primer doesn't stay hard over a few hours or overnight and I have to prime it 3 times before it goes fully firm and I can start it so I'm thinking that's my issue until I can confirm it tomorrow when I check!

What is an external lift pump and how easy is it to add? Is there a thread for it?

I will check all the fuel lines and clamps and under the cargo and see what I find from there on.

 

How do I bleed the air though? This is the main thing.

Thanks for the reply

20201102_204648.png

Edited by bistratoaie
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Read my previous post fully, then search Dronus4x4 posts about NADS on this forum and on patrol4x4.com as well as GU2 user archives and posts about external lift pump there.

VP44 can suck its own fuel from the fuel tank however Bosch made provision for external supply pump (lift) in its reference design as vane type supply pumping section inside the injection pump is very inefficient at lower RPM under heavy load.  

As for that "o" ring  there is no harm putting it there but most Patrols lost their on first filter service as dumb mechanics don't pay attention and Nissan also claims it is not needed.

To bleed the fuel system is self bleeding but gets overloaded if is it continuously sucking air. Prime up until no air is coming out of the filter to pump hose than connect hose and prime more until pressure relief valve opens or priming button goes hard.

Cheers  

Edited by Rumcajs
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  • 2 weeks later...

@Rumcajs

 

I managed to finally get some clear 10mm hose to see if I can see any air going to the IP and relate to the ICV% and this is what I found.

 

**Can't upload videos here at the moment.

 

Video 1: idling (after 3 days of not starting it);

A couple of little bubbles in the line to IP but then was all just diesel flowing through, watched it for about a minute and no bubbles.

ICV% was at 34-38%.

 

 

Video 2: holding revs @ 2000prm correlating to ICV% values;

Still no air that I can visually see but after turning the car off the primer took 2 pumps to become fully firm again (maybe air getting in before the filter?)

The ICV% values were at 42% @2000rpm then spiked to 57.8% when decelerating then stayed around 35% on idle again.

 

How do these figures sound? Still no error codes just for EGR.

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That hose look clear so to me it doesn't have an issue with air in the fuel. 

However those ICV% are very low. At idle it should be around 50% as a minimum. Mine has around 63% with additional lift pump.

ECU Talk creates log of your gauges as A CSV file is a Comma Separated Values file. All CSV files are plain text files, can contain numbers and letters only, and structure the data contained within them in a tabular, or table, form. I open mine in LibreOffice spread sheet to have nice collums.

See here ==> https://www.ecutalk.com.au/ecutalk.aspx

The key is to select only a data (gauges) you need otherwise it is too much and can get corrupted. Log file is created usually in the same directory ECUTalk runs from.....

B/R

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Well, that might be possible(mine primer button is rock solid after several hours of engine being off). Fuel delivery system on my car is heavily modified and I'm not 100% sure that could also influence it.

Fuel system on ZD30 seems self priming and as such will have a pressure drop once the engine stops. What the residual pressure if any is left I'm not sure. On fully closed fuel injection systems running at around 150 to 200 kPa delivery pressure the left over is about 50 kPa because fuel lift pump has non return valve built in to retain the residual pressure. The trend on self bleeding fuel systems is opposite they drop the pressure to 0 kPa because those systems have a small orifice after the pressure relief/regulator valve so there is a constant bleed off while engine is running. Those systems do have however external high volume fuel delivery lift pumps usually gear type. 

Looking at the design of VP44 system it is kinda weird cause it doesn't contain fuel bleeding nipple at the either the filter or the injection pump fuel gallery which suggests it isnot fully enclosed system and by having internal fuel lift pump one can't tell if there are non return valves of sort in there.....(note bellow is a image of 6 cylinder version of VP44 but essential components are the same e.g. 4 cyl version has just 2 high pressure plungers...)

vp-44final_6_cylinder_engine.jpg.cec4eab1c1715585aab03e1a36a5e0f8.jpg

 so it basically purging air only after enough pressure is generated by fuel and relief valve starts to unload...

So it is possible the filter head contains non return valve therefore if it is leaking it allows fuel to drain back to the tank.

Nissan_VP44_cutaway.jpg.d8feda6510292a2a57be3f91484a50b1.jpg

I have had no privilege of dismantling fuel filter head yet on Nissan so I don't really know. I'm very familiar with heavy vehicle diesel engines fuel systems and variations of non return valves vs self bleeding restrictor/orifice in the fuel return line is mandatory. These engines do use separate geared fuel lift pump (like ZD30 common rail version) because fuel volume and feed pressure requirements are much higher (around 500 kPa).

What is clear from your issues is that fuel delivery in to the IP (injection pump) is compromised. Low ICV% are also result of blocked fuel filter, restriction in suction line this part is very difficult to identify. If Nissan included some kind of screen/sieve in the fuel pick up pipe and that is restricted with debris could should also be not discounted. 

One way of seeing that is to make you own temporary "fuel tank" with the jerry and direct hose to filter housing to see what happens to those ICV% or indeed primer on the fuel filter head.

B/R

 

Edited by Rumcajs
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  • 2 weeks later...

@Rumcajs thanks for the helpful info!

Just an update:

 

I ordered a set of Bosch metal tip glow plugs and installed them all which went well, making sure to clean any oil or anything that was on the cam cover, checked the seals and they were all fine too, cleaned and wire brushed the rail too so it was nice and shiny and made sure it's not earthing out anywhere on the cover! Contact cleaned the connector and measured voltage to it (12.3V with ignition on) so it's getting power.

Also installed the PowerTrain Glow Plug Timer mod which came up a treat, weather is warmer now so only need a few seconds of glow/afterglow and my starting issues are all under control and it fires right up everytime! 😁

 

I ordered a replacement primer pump with a bleed screw and that came with a new seal that sits around the thread and installed that too, the old one was definitely leaking air from the diaphram inside because I could hear it when I took it off to replace it, I pumped it while blocking the fuel inlet side and was a very slight air leak I could hear so that was a problem.

With the new one in its now starting perfectly as well as staying firm overnight! No more air issues for me 😁 am yet to corelate the ICV% values with the new one once all the air has self bled from the system and I can create a log on ECUTalk.

 

Still not sure how to open the log file?

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Good stuff, thanks for the update.

You can open the log file either with Wordpad, or spreadsheet program like e.g. Libreoffice Calcs which makes it much easier to colerate.

To get the log file you need to double click the gauge during the preselection, just don't select too many only important ones e.g. TPS%, RPM, AFM, ICV%, Vehicle speed perhaps. No need for voltmeter, spill valve, glow relay, A/C fan or  barometer....

Regards

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  • 1 month later...

@Rumcajs

So just to revive the thread back again, my original "hesitation" issue was the fuel cut from the ECU due to the MAF voltages being too high. Also managed to open the log files finally they started working properly and I could read the data!

 

I have fitted a HPD boost controller just after I did the glow plugs and had it set to around 18 psi, it would occasionally hit 20 psi, I had a beep set on my gauge for an overboost warning but she drove fine. I had no issues since doing the work on it, even took it for a 4hr trip one weekend up and down windy roads etc and all was great, EGTs were good barely reached 400°c.

 

The other day on a 50 minute drive to town, it started to hesitate just a couple of times and slightly, I was quite annoyed because it was very unexpected. I immediately pulled over and luckily had some tools in the car and I turned down the boost just a bit (16 psi) to try and avoid hitting the fuel cut. I still managed to get to town and bought some MAF cleaner to give it a good clean when I got home. On the drive home I only could manage to get to 80kph, I don't think it hit fuel cut but it was constantly stuck in a limp mode.

 

When I got home I took the MAF sensor out and gave it a good spray to clean it, I also replaced all the vacuum hoses for the boost/turbo lines as some of them were old and frail from rubbing etc and made sure they were all on tight and zip tied, I also double checked the boost controller was set right and I am hitting 16 psi. Took it for a drive and it was behaving nicely didn't hesitate/ hit fuel cut but I'm wondering what the best option is to remove fuel cut/limp mode?

 

I know they don't make the jaycar voltage modifier anymore and I'm not too sure about adding a diode/resistor in the MAF wiring, I have also read about the turbosmart FCD-2 as an option? I also know HPD make an upgraded MAF housing which apparently increases airflow by 30% and eliminates limp mode but I am a bit skeptical about spending $250 right now unless I know it's going to fix the problem, anyone have any ideas/solutions?

 

Thanks!

Edited by bistratoaie
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Gday,

Short answer is nothing works to eliminate fuel cut function from factory ECU. Need to remap the ECU to fix that issue.

Don't waste $$$ on HPD gear, doesn't work especially MAF housing, I've got one, it creates more issues then it solves.

Don't use FCD2 boost controller too, it doesn'twork.

Over the time I've done it all. The only thing that worked is re-maped ECU. Then you need nothing else. 

The way fuel cut works is based on several factors: RPM, MAF airflow,  time and TPS. Turbo boost is not taken in to consideration!

E.g if RPM is bellow 2000, TPS over 30%, MAF above set limits for longer then 6 secs it will fuel cut to keep boost bellow 10 psi until reset.

Another RPM point is @ 2700 and another at 3400. Its imposible to deal with. If you quickly release accelerator pedal it will reset.

I obtained another ECU from https://ecpt.com.au/ and had it re-mapped and now my only problem is to keep the black smoke pouring out on take off  behind me and backing off cause worrying about breaking something with that much power! The one and only mod, no need for anything else. Oh it will also expose weak clutch and shitty cooling with that much more fuel going in.....

No need for boost controllers either, factory solenoid is enough.

Regards

 

 

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Thanks @Rumcajs

I thought the HPD MAF housings & upgraded air intake kits were bigger to allow more airflow thus not allowing the MAF voltage to reach the limp mode? Or is it the other way around, bigger internal diameter means more air which means a higher voltage reading?

Ah, I was reading that the Turbosmart FCD-2 basically clips the voltage to say 3.99V so that it cannot go into the limp stage? If it doesn't take boost into consideration, it says in the manual to either hook it into the MAF signal wire to the ECU or the boost sensor signal wire depending which one sends the signal to the ECU. Isn't the factory solenoid limited to 16psi roughly?

So I can buy an ECU from East Coast Performance Tuning and get them to remap it or send mine to them to remap?

How much did it end up costing you if you don't mind me asking?

Screenshot_20210119-092013_Drive.png

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HPD MAF housing reduces airflow rate around the sensor. This has severe consequences to fuelling at lower RPM so the car is absolutely gutless on take offs. It is horrible to drive like that. I had to use voltage modifier to offset the signal loss to gain the power back. Totally stupid!

As I mentioned earlier the voltage limits for fuel cuts are variable so fuel cut defender can only work on max values therefore useless!

The factory boost solenoid is PWM valve therefore limitless, its the ECU which imposes limit.....

The ECPT used to have an options,4 years ago, send them your ECU to remap (~$500) or get second hand ECU from them remaped.(~$850) with immobilizer chip disabled. I chose that option in case something goes pear shaped later. Remap removes fuel cut limits, increases power phenomenally as well but sadly he did not figure out (then) the timers for glow plugs otherwise it would be perfect. Mine boost to 24 psi,regularly sits on 19 psi on average but I use dual boost control with manual overide, low to 14 psi for city eco, high for highway/power.

I still use voltage modifier for smoke control (poorly) and left HPD MAF housing in there too cause I have it.

Of all the mods I wasted time, effort and money the remap ECU was last and the best. Now I need to fix my cooling system.

Cheers

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@rum678

Thanks for your detailed experience!

I'm quite confident to go for the ECU remap and I will be giving them a call today to discuss options, although I am in Victoria. If I get it remapped, do I have to remove the manual boost controller as the ECU will manage the boost properly?

As I mentioned, I dropped the boost to 16psi via the boost controller and have not had fuel cut since, I occasionally get cold limp on early morning drives to work (I'm up at 5am), but once I let off its back to normal, I can't see the MAF voltage in real-time, have not yet bought an ECUtalk display unit which I will be doing very soon.

Does the grub screw limit the boost via the actuator? Or does it control the spoolup rate of the turbo? Do I have to adjust it when using the manual boost controller?

It's unfortunate I can't get my hands on a voltage modifier, judging by what I've read they seem like nifty tools to "tune" the vehicle with some impressive results!

If I post a couple of pictures, would you be able to tell me if the boost solenoid is hooked up correctly in terms of the vacuum lines? I bought some 4mm port blocks and put them on, I think it's the right way but you seem to know ALOT more than I do about all this 😅

Thanks mate 🍻

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I would caution you about fiddling with the grub screw on the turbo charger. It is normally set up to optimize flow rate of the turbine during manufacturing assembly using very specialized one off test bench. No one else has it. There is a bulletin out  from Garrett confirming that once you fiddle and affect settings it is rubbish bin for the turbo! So don't do it!

You will gain nothing by playing with it especially if you gonna do ECU re-map. The actuator is controlled by the ECU  and the grub screw is max stop for the vanes opening. ...

You can alternatively  leave the manual boost controller in there you just need to bump the max higher to take advantage of the re-map. The factory solenoid can be utilized as well and some report that it works even better without additional interference from max boost limiter.  ECU is much better at controlling the spool up. 

You could also get commercial  version of the MAF voltage modifier, it has better abilities then Jaycar's as it can store several different tunes which can be switched on the fly.  ===> see Ultra Air Fuel Controller- UAFC  unfortunately it appears no longer available.

My setup is much more complex and it is result of adding of various solutions then combining them together because I had them. If I only got remapped ECU with factory boost controller that would enough.

My list:

1x Dawes valve set to 14 psi for max low boost, (Eco/Cold engine mode)

1x Tilix valve set to 24 psi for max high boost, (Power mode)

1x needle valve to set persistent spool up rate (instead of factory solenoid)

1x switch over solenoid between low/high circuits

1x overide 3 way switch  Auto/Low/High  (Auto functions utilize voltage switch getting signal of the TPS at approx 22% it switches from low to high and back.) 

1x Jaycar Voltage Digital Modifier (JVDM) to tune out MAF voltage at specific range to minimise smoke and improve the HPD MAF housing induced loss as well as limit the output at higher revs)

It is ironic that I now use the stuff to limit or make safety barriers instead of opposite used before re-map.

I still watch exhaust temps gauge like a hawk to ensure I don't exceed 550C and boost gauge not to exceed boost bellow 2000 RPM over 12 psi (mine will take it to 18+ if I push it) which is to protect turbo from stall condition and destroying it.  The remap basically removes all safety and smoke barriers so it is up to the driver to be disciplined otherwise it will fail very quickly cause the torque delivery is like punch from the sledge hammer.  Very impressive when experienced first time but you almost feel the prop shaft twisting away.....LOL.  

 

 

Edited by Rumcajs
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  • 3 weeks later...

@rum678

Hi @Rumcajs

I just received my remapped ECU today and was looking forward at having the time to install the new tillix and needle valve but time ran short in-between work so I'll finish it off after work today.

Can you help me with some info/pics on all the vacuum lines install of the tillix and needle valves. I have read the PDF manual containing all the instructions but they don't make sense for me, I'm lost with a few lines and also where the dampener comes into play.

Any help would be much appreciated, then I can finally plug in the ECU and drive it 😁

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G'day,

I strongly urge you to just use factory boost controller solenoid first with your remap ECU.

There is really no point to have needle valve and or Tilix in there as all the limits were removed.

If you want to experiment then OK but it is kinda not needed.

You could include Tilix valve with factory boost solenoid to limit max boost I guess:

1120242158_StandardDawes.jpg.81777c0ed0b03e57aa45dd20a8ce86f5.jpg

Tilix valve/Dawes valve have same principle.

Or if feeling adventureous you can remove factory boost controller completely:

1610482829_NV_DW_BoostControl.jpg.ff6c9d689118540349b2ca7860bd6843.jpg

 

But you will need to fiddle with right adjustment of needle valve and that takes time; trial and error!

Here is my setup:

1583059510_2StageBoostControl.jpg.d4e9749f05a0dafe76cc2a273feb0b72.jpg

I progressed through all above stages eventually but that was before I got remapped ECU.

I left it there cause its there otherwise factory boost control is sufficient once the limits are removed.....

Regards

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@Rumcajs

No worries thanks for the info!

I have mine now set up like the 2nd diagram you sent me, with the tillix and needle valve bypassing the factory vacuum solenoid and the vacuum cannister removed.

It runs beautifully with no more limp or fuel cut and doesn't struggle going up an incline like before.

I haven't yet experimented with the vacuum solenoid and just the tillix to limit the boost but I was told by the tuner to use tillix and needle valve. I guess I can experiment and try with the vacuum solenoid if you suggest so and see if there's much difference in performance and drivability.

Thanks again!

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  • 4 weeks later...

Back again lol

So about 2 weeks into having the remapped ECU, everything was going perfectly fine so I was happy. Then one day the missus and I decided to take the Patrol into town about 40 minutes each way. On the way there, it drove great with no issues. On the way back about 10 minutes from home it jerked/hesitated just a couple of times, I was very annoyed by this as you can imagine. When I got home, I checked the codes via ECUtalk and had a code 0406 AIR/INT volume - excessively high signal from MAF sensor and of course the EGR code.

So, I got in contact with the people who did the remap and they run me through a few checks, I mentioned that the MAF sensor was replaced maybe 2000 kms ago. He mentioned it sounded more like a fuelling issue rather than limp mode (due to high boost) and then asked me what brand it was and I said Nissan OEM but it seems I bought a fake one on fleabay that was a Nissan OEM branded one not the genuine Hitachi ones they come out with from the factory.

I ordered the right Hitachi one and just received it this Monday, disconnected the battery and took the old one out and they did look a little different. Put the new sensor in and connected the battery a little while after. Before doing test drives, I checked the MAFv via ECUtalk.

The old sensor ranged from 2.16-2.18v @ idle

The genuine Hitachi sensor ranged from 2.1-2.14v @ idle (that’s a little better already)

But when I took it for a drive to the Post Office 15 minutes away, on the way home the missus said she felt it jerk again, it didn't do it bad almost barely noticeable but she noticed it. I thought I'd have a look for codes again once I got home so I connected the ECUtalk cable and again got the same two codes, 1003 EGR and 0406 INT/AIR VOLUME. I was surprised because it was a new genuine sensor with already lower MAFv readings than the previous fake Chinese one but it must somehow still be reaching MAFv above the threshold. I thought the remap was meant to fix all this or am I wrong thinking that?

I did play around with opening the needle valve to try and slow down the spool-up rate but it didn't change the fact I was still getting high MAFv and it just made the car a little more sluggish. I have read about small amounts of oil vapour heading back to the air intake and in turn contaminating the MAF sensor if you don't have a catch can fitted which I DO NOT at this point in time. Could that possibly be causing my issues with the higher voltages? I have seen a small amount of oil in the intercooler pipes a week or so ago when I took it off to replace all vacuum lines so I cleaned all that up but maybe I have oil contaminating my new MAF sensor giving the ECU higher readings than what they actually are and causing the fuel-cut problem?

Any help is appreciated, cheers!

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