D22, 2007, ZD30, New inj pump, new injectors -Still no torque!!

[Tom21]

hi all
My son bought a 2007 D22.

150K's, EGR mod, snorkel.
Starts great runs well. Been to the mechanics more times than we care to remember. They al said lack of power was injector pump. 4 months ago we replaced injector pump $3500. No difference. LAst week we did injectors ($1800). They were worn and we gained another 10kw on the dyno (now 62kw). Runs better on the straight. Gets to a hill - hopeless!

Turbo seems to boost OK but late 2700-3000rpm.

Second mechanic has been all over it (hes great), swears turbo is fine - reckons its the Inj Pump.
Thinks ECU is fine as the car starts and runs great - just no guts.

This maybe a separate issue but fuel consumption went from 10l/100km post injector pump but pre injectors to 17l/100km after injectors were replaced.

I have attached a DYNO printout. GREEN is pre injector pump replacement. RED is post injector pump AND injectors replacement.

Be interested in ANY advice/opinions - its doing our heads in (and wallets)

regard sScott

 

[rastik86]

Have you tried unplugging the Neutral Position Switch? Search for it on the forum, there should be plenty of threads.

Two tests I've read are while driving in 3rd gear, gently push the gear stick to the upper left and if you get more power your NPS is shot
OR turn car on let idle, turn "Heat" switch below steering wheel RHS on, revs go up to 1200RPM, foot on clutch and put in gear leave clutch in and go through all gears, if revs don't drop when you put in any gear NPS is shot.

Or you could just unplug it and see of it goes any better.

From what I've read, if you take the rubber boot off under the gear stick over the transmission it is more easily reached than trying to get at it from under the car. Apparently it is a blue plug and you will know you have the right one if you turn on the "Heat" switch below steering wheel RHS next to drivers door and nothing happens. If the revs raise from normal idle to 1200 RPM you have the wrong plug.

 

[Simsy]

The 3lt d22 was around 110kw from new at the fly you will lose around 30% by the time it gets to the wheels and a bit more for the 150K its done so the dyno run is not that far off. I would give rastik86's suggestion a try. After that I would look at a good chip my old d22 had between 120 and 130kw at the wheels with a 10 stage chip set at 6, once it hit 2000rpm it just took off. I thing to remember this is a heavy car with a small diesel motor so its going to be slow on the hills.

 

[Old.Tony]

As above. I'd be surprised if it's not the NPS. Surely the guys have been all over fuel delivery already, bled the fuel system, checked for no air in the fuel - but they may not know about the neutral position switch issue in these cars.

If memory serves, the NPS is required for some 4WD operations (can't remember clearly, I shouldn't try answering technical things when I'm on my 2nd case of beer for the evening). If you're not going 4WDing, just rip the bloody thing out (disconnect it).

If it's not the NPS, it could be the CAS (although I'd be surprised if they hadn't checked this). The CAS signal is responsible for telling the ECU where the pistons are, so that the injectors are opened at the right time. Getting it wrong will reduce your power and increase your fuel consumption.

It's interesting that the fuel consumption has risen dramatically after the injectors were installed. Not sure if that car needs the injectors registered properly with the ECU, although I'd have thought it would throw a fault after a while.

There are other things to think about - issues with the spill valve or such. I'd try that NPS first, it's a bloody cheap fix - besides, I've typed enough and want to get started on the 3rd case.

 

[rastik86]

I thing to remember this is a heavy car with a small diesel motor so its going to be slow on the hills.

Too true. They were never meant to be a race car, but are a great workhorse.

Edit: My 4.2TD GQ Patrol used to be out gunned on hills by the blokes I worked with in the ZD30 Navara company cars, but that didn't change the fact they didn't like hills

 

[Rumpig]

Zd30 injectors don't need to be registered to the ecu, they're mechanical not electrical. Westo had his stock D22 dynoed after having lack of power problems ( dodgy fuel filter leaking air ) and it was 58 kw after they fixed it so yours is about right. I'd suspect NPS and it's easier to get under the car and seperate the plug than it is to pull the gear stick boot off.

 

[rastik86]

... it's easier to get under the car and seperate the plug than it is to pull the gear stick boot off.

There you go! Which plug is it working form engine end, a photo might help the bloke out if anyone has one

 

[Rumpig]

Crawl under the drivers side, theres 2 switches up high and one a bit lower and towards the rear on the side of the gearbox. The NPS is the second one back from the engine ( the one with 2 white wires in the pic ) just seperate the plug. With it unplugged when you turn on the heat switch the revs shouldn't rise to 1200 rpm.

 

[rastik86]

Good work Rumpig. Let us know how you get on Tom21

 

[Tom21]

hi all
thanks for all the replies! i appreciate it. Will try the NPS. MAF sensor was also replaced with th einjectors.
He checked th efuel system - fed it from a bottle etc
Does anyobne know how to check the crank angle sensor ? computer i guess. o r can i check a voltage somewhere?

thankls again - keep ya posted
scott

 

[bods]

Nissans consult system is likely to be the only thing that will tell you whether the cas is working properly... If disconnecting the NPS doesn't help, it could be the wastegate creeping open and loosing boost, has he got a boost gauge on it? Lack of boost would cause lots of black smoke under acceleration and excess fuel usage as well as feeling down on power... There are also a lot of other factors a dyno doesn't tell you... Could also be heat soak, if it does t have an intercooler fitted and is a reasonably hot day it will feel down on power as you are getting less air in the cylinder each stroke when the intake temps are higher.

 

[Tom21]

hi bods
thanks fort hat. no smoke ever. i attach a dyno readout. mech thinks boost is AOK. seems consistent on the graph. he has a boost guage. boosts out at about 14 on the guage. seems close to dyno.
ill try the NPS. going back to mech on monday . ill mention the CAS.
the high curves are the boost, lower one sthe air to fuel ratios
cheers scott

 

[Old.Tony]

Boost seems ok to me, they don't run much higher than 15psi on those engines. I think you can get them to boost up to about 17-18psi safely, but after that there are risks (impeller stress among them).

My concern with the CAS isn't so much with the engine's power, it seems to have the power it needs, but the fuel consumption just seems a little high. Most YD25 D22 drivers were reporting much lower fuel figures than that (and ragging on us D40 YD25 drivers who had 12-13LPHK in the city).

 

[Rumpig]

It seems odd that the AFR went from 20 up to 25-1 when fuel consumption went up, AFR should have gone down.

 

[Tom21]

Thanks again guys.
Yeh seems odd alright! Taking it back to nissan on Tuesday to get them check the pump properly

 

[Rumpig]

Check to make sure your oil level isn't rising, they could of cracked the spill line and the extra fuel is going in the sump.

 

[tweak'e]

you mention egr mod done.
have you done the butterfly mod?
the increase in afr could be butterfly opening.

also in the graphs what speed is what rpm?