Loss of acceleration D40

Nissan Navara Forum

Help Support Nissan Navara Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Brodska

Member
Joined
Apr 15, 2012
Messages
11
Reaction score
3
Hi everyone,

Long time since I have had to ask for help can usually find what I need so i'm sorry if this is a double up thread.

I have searched and searched different ways but cant find a similar issue or wording it incorrectly. I have an issue which had started around 10000k's ago and has been intermittent and impossible to this point for me to diagnose as it happens in usually very inconvenient times.

Today i was lucky/unlucky enough for it to happen 3 times in a place to pull out of traffic: now for the problem what happens is I can be accelerating changing gears or trying to take off from a stand still and I will instantly lose all throttle/forward momentum and glide to the side of the road, engine still running and no error codes. Since I was not stuck at a give way I pulled up the ODB2 Scan and could see that it was registering the push on the pedal to accelerate but no movement on anything else (attached a screenshot). A quick off and on again and away ago, today happened almost straight away again but after a 2nd restart it was fine.

My first thought was a fault with the accelerator electrics but it still registers with the ECU so now I am unsure.
I haven't tried an ECU reset, will be doing a service this weekend and plan to reset it then if there are no other solutions to try it.

Any help would be greatly appreciated.

2009 D40 RX Spain Built
Manual
205000km just on the clock

Happy to provide any more info if it will help.
 

Attachments

  • Screenshot_20220713-130543_Torque.jpg
    Screenshot_20220713-130543_Torque.jpg
    198.1 KB · Views: 0
Observations: coolant temp is low (glow plugs should still be on), revs just over idle, fuel rail pressure looks right for the revs. With that much throttle commanded, you'd expect something more than 825rpm. No boost, but at those revs no surprise there.

I'm wondering if it's SCV. How long since you've put a bottle of injector cleaner through it? It's possible the SCV has given up.

Does it start easy, even when cold, or does it take a fair bit of cranking?

Have you cleaned the MAFS?

There's no drama with the throttle. Turbo isn't involved at those revs so ignore it. The problem is either:

1) Fuel
2) Air
3) Timing

Timing could be an issue with a faulty crank angle sensor (has happened). That it resets itself after a power off though, that's usually the sign of a crook SCV.

Small device sits on the side of the pump (lower on vehicle's right side of the engine), 1 electrical connector and 2 torx screws hold it in place. Earlier models had the "short" SCV which had more problems than the "long" one, but I'm not sure yours would take a long one.

Usually get some reasonable improvement with injector cleaner thrown at it, but that may only mask the problem for a while - depends on the condition of the SCV. It might be scored/pitted. Pop it out and take a squiz, if your hands are ok (mine aren't) it should be a 10 minute job.
 
Cheers @Old.Tony,

Starts no drama even cold -1 degree mornings handles easy.

Injector cleaner through at last service 5000k ago.

Have not done a MAFS clean for a while, will add that to the list for the weekend as well.

I'll definitely pop the SCV out and check it while I'm there.

Thanks for the help will update after the weekend if any success with SCV, problem so inconsistent may take a while to prove a solution.
 
Try this quite typical trigger for the problem: drive the car gently, get speed to about 50-60km/h (in a 100 zone preferably) then plant your foot. If it immediately loses power, pull over, reset, get moving again, same initial speed, then gently (no more than 30-40% throttle) - if you don't have the sudden drop, slow back down a little and hit the gas again. If it stalls again, it's almost certainly the SCV.
 
@Old.Tony
Thank you for your help, I was able to check the part no. of the SCV and was in stock at the local Repco, Installled, reset ECU and went for a drive. Been about 1.5 weeks and no sign of it happening again plus the car seems to be running so much better now which is an added bonus.
 
I am having the same problem.
The only difference is mine will go 100% throttle input with no engine increase in revs but only on 1st gear with clutch out ( accelerating from stand still) as soon as I hit 2nd through to 6th it is perfect.
No codes coming up on OBD scan tools and no idea as this is my 1st Nissan.
 
I am having the same problem.
The only difference is mine will go 100% throttle input with no engine increase in revs but only on 1st gear with clutch out ( accelerating from stand still) as soon as I hit 2nd through to 6th it is perfect.
No codes coming up on OBD scan tools and no idea as this is my 1st Nissan.

Try something to see if it makes any difference: put the car in first, and as you start revving the motor, move the gear lever to the left, then to the right, and if neither of those work try pushing it further forward and gently back without popping it into neutral. If any of these actions "fix" the problem, it's your NPS in the gearbox. The instant cheap fix is to unplug it.
 
I have finally been allowed to drive my car again (Surgery stoped me). I have worked out the NPS is faulty due to holding the gearstick to 1 side and getting the Cruise Control to work again. So i am going to unplug it and see iif the 1st gear thing happens again.
 
I had this same problem and it turned out to be the ESP control. The car thought its wheels were sliding and cut the power to the engine. It was intermittent but on the motorway would make me stop and have to restart the engine. Took ages to diagnose but replaced the sensor and all is well since.
 

Latest posts

Back
Top