Low end umphf - or lack of

[YBOD]

Have a 2012 D40 ST manual and not being a too mechanically minded I may not describe my problem (or probably just a niggle) as other might be able to but here goes.

At low revs (less than 1000revs) on a slope (and not necessarily a very steep slope) and in first gear the truck seems to have no umphf or go about it. It will pull away from a standing start say at a junction or traffic lights but without a foot load of revs it feels like she is in second or third gear even though she is in first. Eventually once the revs build up (or I give it a foot full of gas) it picks up and pulls away but not with any great gusto.

In addition, I used to have a Landrover series 2 and if you put it in any gear but let your foot off the gas she would usually move along at a crawl just on idle. The D40 on the other handle simply stalls. And driving up steeper slopes in first it doesn't have the guts to get up from a standing start and either needs low ratio or a good run up which doesn't lend I self to carefully creeping up trails.

She's ok pulling away on the flat and I appreciate that being deisel she is never going to perform like a petrol but surely it should have more guts.

Is there anything people could suggest to improve low end grunt or is this just something I have to live with?

 

[Rumpig]

Your not the first to use that exact description for the YD25s lack of power down low. Most obvious fix is an exhaust and chip.

 

[andrew0]

Exhaust didn't help me down low, I usually rev it to around 1500 then pull the clutch out, let's the turbo spool up nicely. You can get a high flow turbo from forefront that has had a noticeable improvement in turbo spool. Our motors won't work well without boost.

 

[andrew0]

I haven't got a forefront turbo, only heard good things about them btw.

 

[mike1303]

exhaust and EGR fixed my problems.
The chip did as well, but fried my clutch. so i substituted it for a Windbooster and Shes a dream to drive now

Definatly start with the exhaust, and if you like it loud discard the muffler straight away

 

[Cobez]

exhaust and EGR fixed my problems.
The chip did as well, but fried my clutch. so i substituted it for a Windbooster and Shes a dream to drive now

Definatly start with the exhaust, and if you like it loud discard the muffler straight away

What he said ^^^

 

[YBOD]

Firstly, thank goodness I'm not the only one. Phew

I've done the ERG mod and already had to replace my clutch so in rush to go down the clutch frying route.

So what is a Windblower?

 

[Old.Tony]

Must be something about the manuals. On flat ground with the 2.5T caravan behind, if I take my foot off the brake my Navara will start rolling forward at idle.

Sure, it's no race car. Nissan sacrificed power in the bottom end of the rev range to provide more power in the top (that's the way turbos go) so they could keep the "most powerful tradie" moniker. The only real way to change the power curve is to change the fuel mapping, turbo AND the turbo control.

 

[lookskyward1]

First gear on the manual is really too tall, it could do with being a lower ratio especially when towing. A tuning chip will make a difference in power delivery as may the special EGR plate sold by yd25.com

 

[fzrr]

Yep I got the same problem in my D22. Gotta ride the clutch a bit on the hill starts otherwise it bogs down and I have to put the clutch in and go again.

 

[boostin_7]

Hi YBOD, I've got the same model as you and do notice the same when there's some kind of resitance like a hill ect.
On flat ground though shes's fine. I can roll the clutch out with no revs and she'll start moving our jayco camper fully loaded & will just keep going without stalling. Add a hill though and its all over.
I do have the egr plate fitted & removed the airbox baffles.
When the engine/clutch were fresh i could never do this, but at around 30k she started to get easier to drive.
Mike1303 Did you try a muffler delete on the stock system before doing the full exhaust? Im trying to decide whether its worth it as some say with the bigger front section you can loose some low down torque.
Also what chip did you used to have? How does the windbooster compare to the chip performance wise?

 

[bods]

^^windbooster and chip are 2 different things. Windbooster is like a throttle amplifier, it makes the ecu think you have pushed the pedal further than you really have. You can achieve the same result just pushing the pedal harder... A chip on the other hand can do a lot more than just that, as I'm sure you are aware..

 

[mike1303]

I didn't bother touching the standard exhaust system.
Went straight to a 3" with no muffler.

I had a chipit chip.
And I'm more then happy with the windbooster over the chip any day