Would anyone have the Denso (not Nussa) numbers off a SCV? Need to check if have the right one.
They are etched into the body.
The new one I got has, but truck runs worse with that than the old one...
0042
03N-72253

Also, where can I get a list of fault codes for a D40 engine? I need to know how to get the letters too
like P1272... Can't find it on here..

 

Ok, New SCV was faulty. Fitted good new one. Engine now running better. It has boost. boost hoses are pressurised with engine revving about 2500. Reset ECU again with engine hot.
When I drive it up a hill under slight load, its still surging with rev counter is fluctuating. There is black smoke too.
I sprayed soapy water on all the boost hoses and did not find any leaks.
At this stage I suspect that the pump is knackered. Is there a filter in the pump?
Its not the fuel filter, I connected the diesel up direct with no improvement.
Any suggestions before I head for the main dealers :-((((
Might try an Italian tune up tomorrow. I have a good steep long hill not too far away...

 

Hope you get sorted i'm sure someone on here will help. I've had loads of issues with my 07 Aventura 42k well documented on here :shock: . My stealer changed fuel rail before the SCV, no diff with fuel rail, jury still out with SCV.

All i will say is depends how good your dealer is, if they follow Nissan ways it will cost a fortune in replacement parts, i would ask them if poss to fit a V.I (i think it's called) which basically is a box of 'tricks' which records all relevant info, you have a 'hand held' button which you press when your truck goes into 'limp' and they can see what's going on in a 'data' style and rule out from that. I'm unsure from what your saying if it is going into 'limp mode' but if not maybe this sort of investigation could be carried out :scratch:

The 'box of tricks' belong to Nissan so not costing dealer anything apart from time fitting?? Just a thought hope you get sorted :thumbright:

 

Thanks for the reply CP
I don't think it is going into limp mode. It seems to go better cold tho'
After it warms it gets it hard to rev over 2500 unless you floor the boot. It does build speed with difficulty. I can stop and reset ECU and it dosen't go any better so it probably is not limp mode. It has no stored codes just 10 10 10.
There's plenty of black smoke if ya give her boot and she's drinking diesel.
The main symptom is that under load it surges intermittently as if it is starved of fuel.
I have changed the filter and even connected the diesel up direct to eliminate the fuel filter.
I have swopped out the boost valve with a friend, I fitted a new SCV, cleaned MAF sensor, removed the air cleaner, checked the vacuum pipes.
I will try swopping out the MAF sensor next. The boost pipes are pressurising and I have sprayed soapy water on them to check for leaks. Hope it's not the turbo or pump :-((

 

Too much fuel, not enough air/boost...
Have you checked that the lines to and from the vacuum pump haven't been crossed up? It's an easy mistake to make when you work on/near the scv and fuel pump.
They control the boost solenoid and any swap or kink will give you an unresponsive turbo.

 

Thanks for the reply CP
I don't think it is going into limp mode. It seems to go better cold tho'
After it warms it gets it hard to rev over 2500 unless you floor the boot. It does build speed with difficulty. I can stop and reset ECU and it dosen't go any better so it probably is not limp mode. It has no stored codes just 10 10 10.
There's plenty of black smoke if ya give her boot and she's drinking diesel.
The main symptom is that under load it surges intermittently as if it is starved of fuel.
I have changed the filter and even connected the diesel up direct to eliminate the fuel filter.
I have swopped out the boost valve with a friend, I fitted a new SCV, cleaned MAF sensor, removed the air cleaner, checked the vacuum pipes.
I will try swopping out the MAF sensor next. The boost pipes are pressurising and I have sprayed soapy water on them to check for leaks. Hope it's not the turbo or pump :-((

I have exactly the same problem with my Nav, but intermittantly, sometimes it's fine, sometime no power.

Dealer has checked all the pipes, replaced boost control solinoid which cured it for a couple of weeks but now back to square one

Leaves no fault codes, and sods law that it usually happens early in the morning on my way to work - by the time the dealer is open everthing is fine again

Sweating a bit now as the warranty runs out this month, and we are due to go away with the caravan in a couple of weeks. Nav wouldn't pull the skin off a rice pudding when it has the fault, let alone a 1500kg caravan!!!

 

Was funny first time I had it at the dealers

Hooked it up to the computer, no fault codes logged, receptionist came back and said there was nothing wrong with it.

I asked if the tech had taken it for a test drive - 'No - just had it on the computer'

Suggested that they take it for a spin, when he came back - 'Oh yes sir - something definitely wrong!!'

God I miss the old days when mechanics were mechanics, not PC operators and fitters!!!

 

Have a good look at the vaccume system, had a simlar problem wtih mine, eventually found it was a damaged inlet manifold suction valve (down near the oil filter) that was venting the vaccume system

 

I forgot to add in my previous post with the vacuum diagrams that an open, switched or kinked vacuum line doesn't throw a code. That why this seems a likely culprit in this instance.

 

Big thanks to everyone contributing to this thread,

Will give the vacuum system a good check for leaks again this evening. Maybe a little pressure and some soapy water...
@Alex, if you remember, you got me out of trouble recently when I broke the nipple off that valve (number 2 in diagram)
I did not replace this valve as the engine ran fine after this. I blanked off the rubber tube going to it and the one coming off it too
I assume that the intake valve (4) is now not working. Would this contribute to the problem?
That valve would not be a joke to get at...
Also, I think my vacuum pump is different to the diagram. I have a power steering pump driven off a fan belt down there.
Could the vacuum pump be on the engine under the oil filter??

 

Don't use soapy water!
The vacuumline sucks..... really. It sucks. (geddit???).

Yes the vacuum pump is more or less under the oil filter, the two vacuum lines that cross over the engine end up there, you can't miss it.

 

Hi Blue
I understand that, I was going to slightly pressurise the hoses with the engine switched off.
This would show up any leaks. I will take off the front wheel this evening and get a good look/feel around done in there.
One of those hoses crossing the engine is blanked off as far as I can see.
A friend has a navara and the plumbing is slightly different. It has only one hose crossing the engine.
My vehicle is a Pathfinder.
I will report back here....

 

The 190hp version has electronic rather than vacuum/solenoid control over the turbo's vnt actuator, that is perhaps the difference.

 

Ok, checked the whole system again. Took wheel off so I could get a good look.
There are no leaks in the system. Put a bottle of Redex Injector cleaner in the tank and went for a run.
The surging was still there. I drove it very hard on a few quiet stretches to see if an old Italian tune-up would help. It got it hard to get to 120kmh but after a few hard runs the surging was gone. Its not building full power but better.
As mentioned before, during an oil change, I broke one nipple off the valve (2) shown in the diagram.
I did not replace this valve. The nipple I broke off was the one leading to the actuator (4).
So this connection is now open to the air. I just plugged the rubber pipe as suggested by Alex.
The truck seemed to run fine after this before getting bad again. Maybe some vacuum is being lost through this hole where the nipple was.
Does anyone know what this valve does and if it is critical to the proper running of the engine and should I replace it. It is not working as the pipe is not connected.
It looks awkward but could be changes easily enough.

 

The intake control valve is to ensure clean engine shutoff, without it some diesels have some prolonged stuttering when turning the engine off.

I take it you are not losing vacuum, and that the fitting from the pump to this actuator is properly plugged?

 

There is no loss of vacuum when the engine is stopped it least. There could be some when the engine is running as the hole on the valve where I broke off the nipple is still open, I dunno.
I could screw a self tapping screw into it to plug it off to make sure.

 

Not clear if the fitting towards the vaccuumpump is still open, or to the actuator.

The line to the vaccuumpump should be capped, otherwise it's not imparting enough vacuum on the other lines that matter.

The nipple on the actuator can be left open, that will not affect things too much one way or the other.

 

Brought her for a long drive last night. It went ok at first but surging came back on way home.
It go it hard to get over 110 going up hill that it would normally accelerate up so power is down but not gone completely.
It was a **** wet day today so I will double check the vacuum system tomorrow.
Would the pipe to the brakes have an effect? The connection with the diaphram housing could be leaking slightly.
Is it Ok to totally isolate the cut off valve thing 2 and 4 ? Seems to stop ok without this.

Shes still drinking diesel. Computer shows 13 l/100kms its usually around 8.9. Shes an auto.

 

Sorry not been here in a while, The vaccume feed to the intake manifold control valve should be capped where it tees off the vaccume line it sounds like you have done this. My guess would be the problem could be the boost control soilnoid or the bellows on the turbo
If you look at the actuator on the turbo you should be able to see the rod that goes onto the side of the turbo if you start the engine up and get someone to rev it you should be able to see this rod moving, if it does the fault is on the turbo side if it doesnt then its a problem wtih the control side
IF you take the pipe off the boost control solinoid that goes to the turbo and suck it you should also be able to get the actuator to move, if not the actuator is faulty

 

Update
Thanks again to everyone contributing to this...
I did that test Alex. With the engine revved to 3000, If I pull the rubber tube off the turbo actuator bellows, the actuator arm moves ok. The boost pipe is hard too. I have a turbo boost gauge on the way. I intend connecting it up to the vacuum side so I can see if the surging is going on here. If not I can connect it up to the boost side to see if it is holding pressure there. It is a petrol engine gauge with both vacuum and boost.
At this stage I am wondering if I got a tank of bad diesel. There is a bit of diesel laundering going on here.
maybe the pump is shot. I checked with a friend who repairs pumps and he says that the engine would not start if the pump was shot. I will swop out the MAF sensor with a friends Navara over the weekend and see what happens.
Charlie

 

OK, swopped out the MAF sensor. No good.
The surging seems to be intermittent so it could be a bad connection somewhere.
After I came home after swopping the MAF sensor, I checked the ECU for codes.
Sure enough there was codes in there. I was getting what looked like
10 2 10 1 1 3 10 1 10 2 10 1 1 3 10 1 10 2 10 1 1 3 10
Does anyone know what these represent? Might point to the bad connection....
Another issue is the ESP light is on continually now. Truck has a test coming up.
Is there any solution for this? Someone said that it could be a bad earth but does anyone know where?

 

The lack of power issue with mine re-occured this morning, managed to get it straight into the dealers with it still faulting. The service manager and senior tech had a look at it and it seems that the problem is either the vacuum pump or the pipe 'connector' between the vac pump and the boost control solinoid/brake servo

Awaiting a call from them with the final verdict

 

I blocked my EGR.
It was slow as usual for the first few miles but seems to have improved a lot.
The surging is GONE..... Must have been something to do with the EGR valve.
I am hoping the ECU is relearning the cleaner lungs, so keeping the fingers crossed.
Fuel mileage (according to the computer) is better too so looks positive.
Never found a conclusive reason for the problem.
Good luck with yours and keep us posted as the outcome.
Charlie

 

Dealer phoned back at 3pm - 'All OK - was losing vacuum over the connector so we have re-routed the pipe and everything is OK now, your car is ready for collection'.

Collected car at 3.30, drove home all OK, set off out to parents at 5pm, no power.

Phoned dealer straight away, booked in for replacement of vac pump on Monday morning. Drove home from parents all back to normal again!!!!

Extra p!ssed off as we were supposed to be away with the caravan next week!!!!

 

Any update?
My heap is still going but seems to get it hard to reach the 125 I like on the motorway.
Seems to run out of steam when the pressure is on.
At least the smoke is gone. Didn't check MPG but computer says 11.5. It used to show c.8.8 usually
I have my chip connected up again and she's going better with that.
Have her shined up and going looking at possible replacements at the weekend. Pity, I like the truck overall.
With the price of parts and dealer attitude, I will be looking elsewhere this time.
They are probably all the same but...