Turbo Solenoid Valve / Connection of vanes

Nissan Navara Forum

Help Support Nissan Navara Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Mine feels like its OVER BOOSTING and loading the engine up. Some days my turbo will "dose" all day - usually the "power down days". Other times it's spooling and a heap less "dosing"

I'll feel my power kick in, and then drop straight off and need to feed more pedal into it. But I can't be looking at readouts all the time while driving to verify x amount of boost at y amount of revs. I feel like it *may be* the actuator "sticking", but it seems to bobble ok at idle and also move through full movement when revved.

I have considered swapping out to a new Turbo, however throwing $1k on a "it might fix it" project is extreme. Given the cash I've already thrown into it, I'm not keen on splashing anything that's unnecessary. If I can prove it's 100% turbo, i'll swap it out.
 
Proving that it's the turbocharger requires an inspection, if the boost levels and noises aren't giving an indication.

It can be rebuilt. Rebuild kits (here's an example on eBay) aren't expensive. You do have to pay particular care to the oil feed and return lines.
 
OK. After logging my driving, I can see that on a "good" day that my boost goes to and hovers around 17psi when accelerating lightly. This would explain why it feels spritely

On a "bad" day its only 10-11psi (but will jump up the 17 when a lot more pedal is used, but it seems to make revs' and not power....and has a lot more erratic in its readings.)

I am also seeing NEGATIVE boost on heavy acceleration especially when the engine is under load (going up hill and then accelerate heavily). I see 18psi then -0.86psi. At this point I roll out of the accelerator to again see positive boost.

So, from this I am going to deduce that it is the Variable Vane / Actuator causing the issue or one of it's associated components. It's not controlling the boost correctly.

Now - I have a new Boost Control Solenoid, so I can rule that out. I will replace ALL my vacuum lines to rule any leak out (though my hoses are only 18 months old). This will be the one from the vacuum pump. The one from the outlet of the pump the the BCS. The 2 from the BCS to the Actuator and Air-intake and then finally the one on the MAP sensor (on the outlet side of the Inter-cooler).

I will cable tie all connections to rule out any vacuum leak from the new hose connections.

I'll report back my findings. If anyone has any other suggestions, please feel free to jump in.


EDIT - just found this on YouTube.. got to 3:50 on the video. Perhaps our VNT need adjusting and the vanes are too closed?
 
Last edited:
To my disappointment I received myTurbo Solenoid on Wednesday put it on ... and no go.. no turbo boost...just running on the engine on its own.. faulty solenoid, getting a replacement next week I hope, so I cant rule out solenois just yet so ill keep posting once I replace it..
 
Owned a supercharged V6 Commodore for a while and a trick with it was to spray lube on the vacuum actuator rod for the blower to keep it from "sticking". Actuator looked identical to the navara so I have made a habit of giving it a squirt with dry lube or similar when I'm poking around under the bonnet. Can't say if it makes a difference as I've always done it but I haven't had any issues either.
 
Well I changed EVERY SINGLE VACUUM line on the car. From Vacuum pump, all the way across and around to the pressure sensor on the Inter-cooler. There is not ONE ORIGINAL Vacuum hose in the engine bay now - it's all BLUE SILICONE piping. And every single end point is then cable tied on to ensure no leaks.

I also removed the Pressure Sensor on the inter-cooler and cleaned it with Contact cleaner. The stuff that came out was BLACK - so it was clearly coated with oil - a perhaps causing erratic boost information.

I also sprayed the VNT Actuator with Silicone Spray to ensure that it was not sticking.

Now while I noticed it was a little crisper in both acceleration and my boost was less erratic, I am still feeling hesitation - so I am going to deduce that the "issue" is actually with the VNT sticking slightly and then releasing.

So - I can either remove the turbo and clean the VNT and vanes - or live with it...

Happy to hear other peoples thoughts or input.
 

Latest posts

Back
Top