Navara V9X Starting and Power Issues

[Old.Tony]

If blocking the EGR pipe has led to a successful start, there's a good chance the EGR valve has developed a fault - either an actual fault, or a blockage that's causing the valve to be held open. You might indeed have a problem with the turbocharger too - vac hoses are a prime source (and inexpensive to replace, compared to the turbo!) of trouble, and would be the first place I'd look at. You can often spot issues with the vac hoses without removing them - if the hose is no longer flexible (hardened) and turns easily on the connection or has visible cracks then it's time to replace it.

 

[Supermike]

Just a thought here... Is the EGR valve operated by vacuum? I know it has electrical connections for sensors etc but what I noticed this morning when defrosting the truck is that the truck didn't make the usual loud howling noise if you rev it slightly - which I have always assumed to be the vacuum pump as it only does it for 5-10 seconds usually when first starting.... Wonder if its he vac pump itself that has went wrong and lead to all these problems? Once it thaws out a bit I'll go have a proper look and see what I can find.

 

[Supermike]

And we have another problem. Code P242F which going by trusty old Google is the DPF. I think there is a solution here though. 25 litres of petrol and a match..... Oh the saga continues....

 

[Old.Tony]

The EGR valve isn't operated by vacuum on mine (and I've not heard of it being operated by vacuum). It has an electrical connector which can't be removed without triggering the Check Engine Light.

Given the starting/running issues you've had, it would not surprise me in the least to find that your DPF had suffered a little extra. Certain conditions need to be met for the DPF to be cleaned and it would appear that you've been unable to get your truck up to speed/temp to achieve those (normal operating temp, over about 80km/h, engine load light-to-moderate - eg cruising on a freeway). It's something you might try to achieve as early as possible - a forced regen (performed by a dealer) is a strenuous exercise on the vehicle - requiring an oil change afterwards!

 

[Supermike]

Yea I have done a couple of forced regens in a previous life helping and old friend and his garage and I honestly thought I was away to see pistons coming through the bonnet, if the smoke ever dissapated. Thinking I'll remove the DPF and try to chemically clean it. I have heard mixed reviews on the process, appears to work for some and not all but I think its at least worth a shot. My thinking in vacuum is it would explain all the problems, however now thinking about it more. A blocked DPF could have caused all and explain the entire excessive soot in the EGR and associated pipework. It's minus 8 Deg C here just now so I'll maybe wait till the weekend and get the DPF off and see what like. I have heard of DPF deletes as well which I'm not 100% sold on due to the legal implications so worst case scenario I'm going to be needing a new DPF, but I'll try the chemical clean first. Definitely don't want to go down the force regen route. Should of probably mentioned a large portion of my driving is short distances but I do put the old beast through its paces every once In a while to try and keep the pipes clear. I'll keep all updated with the progress.

 

[Old.Tony]

If you hollow out the DPF and replace the sensors front-and-rear with ones from auggie (a user here, he's in Australia) then it would be nearly impossible to detect and your DPF issues would be history. The matrix inside the DPF is quite tough but if you have time on your hands (and a large ceramic-capable drill but plus a good metal chisel, don't ask how I know and I won't tell any lies) you can hollow it out.

 

[Supermike]

Might be worth a shot! Didn't want to pubically inform the greater nation of my intent but I suppose I only use the Navara off road these days and not on the public highways.... I think I'll message Auggie and see what he can do, either that or get it mapped out. My dad goes to Australia every year to visit family so I usually give him a shopping list for the Nav but this year due to the whole COVID issue it isn't happening. We don't have the same availability of parts over here especially for the 550 whereas Australia appear to have loads to choose from.

 

[Supermike]

The EGR valve isn't operated by vacuum on mine (and I've not heard of it being operated by vacuum). It has an electrical connector which can't be removed without triggering the Check Engine Light.

Given the starting/running issues you've had, it would not surprise me in the least to find that your DPF had suffered a little extra. Certain conditions need to be met for the DPF to be cleaned and it would appear that you've been unable to get your truck up to speed/temp to achieve those (normal operating temp, over about 80km/h, engine load light-to-moderate - eg cruising on a freeway). It's something you might try to achieve as early as possible - a forced regen (performed by a dealer) is a strenuous exercise on the vehicle - requiring an oil change afterwards!

Looks like a portion of the EGR is indeed vacuum operated. That will be today's task!

 

[Supermike]

Another quick question for anyone. When you first start your truck, and give it a bit of Revs, maybe 1500-2000 RPM, the truck makes a howling/fan noise for a few seconds then stops. All my Navaras have done this along with my old L200. What is this noise does anyone know?

 

[Supermike]

And another update. Just been out to check my vacuum etc. So I am getting over 700mm HG in vacuum directly off the pump itself at idle. So we can rule that out. When I attached my handheld vacuum pump to the line from the vacuum pump that feeds BCS EGR etc I can pump it and instantly loses vacuum when the engine is on or off. I am getting a bubbling/buzzing noise coming from the BCS. I can't remember it doing this before but equally haven't really paid attention. So the vacuum coming out of the BCS to the turbo actuator is around 300mmHg at idle and still makes the buzzing sound. Unfortunately I can't test under load or with throttle as everyone is out of the house at the moment. What I have also done is removed the vacuum feed line to the BCS and used my hand pump there. Pumped to around 600mmHg and held there steady for 10 mins. So I think I can rule out the vac hoses too.

 

[Old.Tony]

The BCS oscillates at 100Hz in my truck, likely they didn't change that for the V9X (although they obviously changed the EGR control!). Losing vacuum through the BCS may mean the solenoid is faulty (I hate the BCS with a passion, and don't have one in mine any more - replaced with a Tillix valve) or the actuator on the turbocharger (or the vac line from the BCS to the turbocharger) is faulty. Apply a modest vacuum to that line from the BCS and see what happens.

 

[[email protected]]

Another quick question for anyone. When you first start your truck, and give it a bit of Revs, maybe 1500-2000 RPM, the truck makes a howling/fan noise for a few seconds then stops. All my Navaras have done this along with my old L200. What is this noise does anyone know?

my np300 does it is the fan, then adjusts itself

 

[Supermike]

The BCS oscillates at 100Hz in my truck, likely they didn't change that for the V9X (although they obviously changed the EGR control!). Losing vacuum through the BCS may mean the solenoid is faulty (I hate the BCS with a passion, and don't have one in mine any more - replaced with a Tillix valve) or the actuator on the turbocharger (or the vac line from the BCS to the turbocharger) is faulty. Apply a modest vacuum to that line from the BCS and see what happens.

Vac line, actuator and turbo all seem to be working. Manage to get it on boost at 1500 rpm with a couple of pumps of the hand held vac pump I have. Stripped the BCS down, looks like the solenoid is stuck down

 

[Old.Tony]

Not an uncommon occurrence. I replaced mine twice before ditching the thing for a Tillix valve.

 

[Supermike]

Not an uncommon occurrence. I replaced mine twice before ditching the thing for a Tillix valve.

Yea I noticed quite a few posts from yourself mentioning Tillix Valves. Doesn't look like they do them for the V9X though I have sourced a genuine replacement for 20 brick so we're all good. Also started the process of removing the DPF filter, but I have run out of gas and WD40, so awaiting that arriving and these bolts are stuck solid.

 

[Old.Tony]

I didn't think there'd be a lot of difference between the way the vanes operated making the Tillix valve not work for yours. It is, after all, little more than a vacuum-operated spring-loaded valve. Boost pressure is fed in one end and if that pressure is too high it opens the valve which causes the vanes to be relaxed. I would have thought it would fit any vacuum-operated turbocharger - have you given the guys at www.tillix.com.au a bell about it?

 

[Supermike]

I didn't think there'd be a lot of difference between the way the vanes operated making the Tillix valve not work for yours. It is, after all, little more than a vacuum-operated spring-loaded valve. Boost pressure is fed in one end and if that pressure is too high it opens the valve which causes the vanes to be relaxed. I would have thought it would fit any vacuum-operated turbocharger - have you given the guys at www.tillix.com.au a bell about it?

I haven't as of yet, but I'll see what they say. Is the YD25 not a 3 port valve though? Certainly my Euro 5 YD25 was, the V9X is only a 2 port valve and is pulse modulated

 

[Old.Tony]

I'm pretty sure my BCS had three ports on it. I've tossed out the last broken one, so I can no longer go check to be sure!

 

[Supermike]

Just a little update. Weather here has been pretty poor and I'm not one for lying under a truck in sub zero temperatures while it's raining and snowing. Coupled with the subframe bolts being well and truly stuck. Yes I have to take the subframe off to get the DPF filter off due to the bolts being almost non existent due to rust. Need to grind them off or drill them out but sub frame is in the way so waiting for slightly better weather. Might be waiting a while....

 

[Supermike]

Another update for you all. DPF finally removed, broke the exhaust pressure pipe removing it and had to pay £90 to Nissan for a replacement. So with the DPF removed and EGR blocked and mapped out it has now solved the problems and truck starts and also boosts again. Now the next problem, getting error codes P0235 - Boost sensor and P0470 - Exhaust pressure sensor. Also noticed the intercooler was trashed, so have replaced it with a full alloy unit. Truck runs better than it ever did, up until the point you give it full throttle under load. Truck then goes into limp mode and get the codes mentioned previously. Thinking it might be the turbo that has gone, or the vanes are stuck. Although actuator appears to move freely. Any other ideas welcomed as usual.

Mike