How to keep a d22 with 386000kms on it going strong?

[Horatius]

That makes sense to me (which could be a worry lol).

In fairness I've heard this claim from people who sell such aftermarket stuff. Have seen it recommended for cars that are chipped to lower egt's.

The fuel economy claim could be just manufacturer marketing spin also. At least I know the 3 litre Hilux has a reasonable intercooler but uses more fuel than the Nav. Goes a lot better too though (on the highway).

The other thing with top mounted intercoolers is they will offer some cooling on the highway, but punching over 1,100 or so sand hills across the Simpson in 40+ deg, they'll probably do the opposite and be a heat soak. So a front mount would be better.

Seems a lot of trouble to go to though when they work fine as is, and more stuff that can break. Each to their own though.

 

[Oldie]

I won't get into an argument but, I did a bit of research about the ZD30 before I bought my old Nav. From what I could find was, a grenade waiting to go off was for the motors in the patrol. So far, I've had no problems with my old Nav.
I think 476,000K on the clock says it all. Treat is kindly and don't mess with it. The Perth guys will know what Greenmount hill is and I can tow my 13 foot Jayco up that hill in 4th gear and it doesn't over heat.
If you want to mess with the ECU or chips, it's your choice. Don't grizzle when the motor ***** it self.
I've never taken my old gal over 2800RPM. it's not a race car and it has always got me to where I'm going and has never let me down.
And to the best of my knowledge, it is stock standard since build in 2003. Says a lot about Japanese build.

 

[alfric]

Yeah the intercooler has been a consideration only, doubtful I’ll bother. Was a purely a thought to keep bits of broken turbo out of the engine should it have a conniption! Seems a whole lot more sensible to keep an ear out for a failing turbo, now I know what I’m listening for, thats all thats required. About to have a new turbo installed, non-issue for now.

 

[alfric]

The reason it’s still going is because as u say u drive it between its boundaries. Start playing with it, intercoolers, exhausts and whatever and u reduce its life. It’s a diesel, not a race car. Lots of Diesel motors do millions of kms if they are driven and serviced competently. My zd30 is coming up to 300k and has a lot of life in it yet, judging by condition of its oil and smooth running. There is never a reason to rev a zd30 beyond 2700 rpm-which is highway speed- in any gear. Going over that just causes bad fuel economy and temperature issues

Basically and in principle I agree, certainly just looking for reliability not increased performance. I fairly sure a bigger exhaust should do no harm, will keep the exhaust gasses a tad cooler, maybe improve fuel consumption a tiny bit but most of all just let the old girl breath a bit better. It’s been an interesting journey learning about this engine. If it was a petrol engine form 1965 to 1975 i’d be totally ok with assessing it’s health and what needed doing. lol. Been great to get advice and opinions from this forum, very worthwhile.

 

[Boogieboots]

Not sure how the ECU knows to put more fuel in with cooler air/more O2. The ZD30 doesn't have a mass airflow sensor but I don't know about an oxygen sensor or some other way. Air inlet temp maybe?

 

[Old.Tony]

Not sure how the ECU knows to put more fuel in with cooler air/more O2. The ZD30 doesn't have a mass airflow sensor but I don't know about an oxygen sensor or some other way. Air inlet temp maybe?

Possible answer: the heated oxy sensor in the exhaust (maybe). This is often used to detect the amount of free oxygen remaining in the exhaust. It's used in my 2009 D40 to determine:

1) How much reductant (fuel) to inject in the exhaust stroke for use in the catalytic converter

2) Whether or not a DPF regen can occur (not enough O2 = no burn)

3) Whether the system is functioning correctly. This is a big one: the ECU varies the fuel rail pressure by a small amount - only enough to affect the engine RPMs by a dozen or so revs. Your ear can't pick up the change. However, the change in fuel levels (with "idle" air quantities = zero boost) affects the amount of oxygen available in the exhaust. This is checked against the deliberate variations of the fuel rail to ensure that they're in sync. No sync = malfunctioning O2 sensor, which means it can't ever dump fuel for the CAT = limp mode.

It might not be that. In the D40, the MAFS not only measures the air flow rate, but it also measures the temperature - which is about 300mm from the impeller of the turbocharger. Knowing the turbo's characteristics allows you to calculate how hot the outgoing air will be for a given boost pressure (measured on the output side of the intercooler). There's a MAPS in the D22, but I don't think it monitors temps (which is important, more temp = less air molecules for a given pressure), so the only thing left that I can think of is the HO2S in the exhaust.

 

[Erick]

Have to agree with ‘oldie’ This topic has certainly showed a lot of ignorance about internal combustion engines in general. They are a machine that burns fuel and air to produce a turning force-torque. The amount of power produced comes from how many times a minute(rpm) this can occur.
Basic engine characteristics are defined by many things, often a compromise. Cubic capacity, valve stout and timing timing, bore/stroke ratio, even conrod length/stroke ratio, along with metals used give fixed characteristics of any motor. Peak efficiency of any motor occurs at its peak torque. Peak power occurs when Reba and torque multiples gives the highest number(HP-KW). Most engines at peak power are not very efficient, they are just pumping the most air and fuel they can, much being lost thru heat out the exhaust or into the cooling system. Adding turbos, intercoolers, exhausts and whatever will not alter the fixed characteristics of any motor. Just more stress. Motors destruct when inertial forces and /or heat cause metals to fail or tolerances to go beyond spec.
So the whole’ seat of the pants feeling’ that it’s going ‘better’ is purely subjective.
Diesels in particular are developed to run at a certain rev range. Bigger diesels anything from 1000 Reba to maybe 18800/2000. Motors such as zd30 are most efficient from around 2000-2700rpm. Test it out for urself by finding an long incline that can be driven in 4th or 5th gear and see where the engine ‘hangs on’ in the higher gear. Yes Umayyad get up there fractionally faster by revving the guts in a lower gear, but u are not using the engine in the way it was designed. Zd30’s fall off the turbo/torque range at around 2000 rpm. They will pull hard all day every day at 2-2700 rpm and fuel economy will be outstanding. The gear ratios are set up for this and all.
If Nissan really had ur interests at heart it would limit Rex’s on this engine at say 3000 rpm. But then they could not competitively advertise the Peak power to all the consumers out there.
Personally I like that they have taken the time to build a 4wd drive that has no rattles or road noise and a lovely motor /gearbox combo that is a pleasure to drive when used the way intended.

 

[redkite]

Not sure how the ECU knows to put more fuel in with cooler air/more O2. The ZD30 doesn't have a mass airflow sensor but I don't know about an oxygen sensor or some other way. Air inlet temp maybe?

As far as I know, the ZD30 only has a boost pressure sensor on the inlet. Together with the swirl valve position (of course, the ECU assumes no EGR block has been added) it guestimates the air flow from there.

Thus, if you try to take off in fifth, and automatically floor the pedal as you hear the RPM dropping, it will inject heaps of fuel that don't burn as there is no RPM or airflow. And it will blow a nice cloud of soot.

 

[tweak'e]

Not sure how the ECU knows to put more fuel in with cooler air/more O2. The ZD30 doesn't have a mass airflow sensor but I don't know about an oxygen sensor or some other way. Air inlet temp maybe?

it doesn't. you get a bit more power because of better and earlier fuel ignition, but thats about it.
its more about tuning the ecu so it expects that it can burn a certain about of fuel. this of course means you need to leave a wide safety margin. just like old school mechanical injection.

 

[tweak'e]

Diesels in particular are developed to run at a certain rev range. Bigger diesels anything from 1000 Reba to maybe 18800/2000. Motors such as zd30 are most efficient from around 2000-2700rpm. Test it out for urself by finding an long incline that can be driven in 4th or 5th gear and see where the engine ‘hangs on’ in the higher gear. Yes Umayyad get up there fractionally faster by revving the guts in a lower gear, but u are not using the engine in the way it was designed. Zd30’s fall off the turbo/torque range at around 2000 rpm. They will pull hard all day every day at 2-2700 rpm and fuel economy will be outstanding. The gear ratios are set up for this and all.

i suspect your referring to the patrol version.
navara version in stock form is very under fueled in the lower rpm range. hence it has a peaky power band, typically 3000-3500 tho this can be extended with mods. sub 2500 rpm they are very lazy.
once intercooled and chipped, they drive more like a normal diesel with proper low down torque.

 

[Erick]

Some people never get the whole power versus torque and efficiency thing. Maybe google could help.

 

[BarneyB]

it doesn't. you get a bit more power because of better and earlier fuel ignition, but thats about it.
its more about tuning the ecu so it expects that it can burn a certain about of fuel. this of course means you need to leave a wide safety margin. just like old school mechanical injection.

Exactly. Diesels with a charge air cooler make more power because they were designed & manufactured with it. Slightly denser air charge across the range and slightly more fuel injected....from the design.
Adding the cooler to a non-cooled engine (and changing nothing else) will have a pretty negligible effect unless the control systems can recognise the difference.
But adding the cooler primarily as a 'broken turbo strainer' has merit

 

[Been a while]

If in doubt, water meth inject that baby and floor it! Flooded or not life begins at 3000rpm !

Yup,,performance, better burning fuel, more efficient, better economy under continuous speeds revs etc. Cooler air, more oxygen dense,, they say.. Thats why i love driving mine in the mountains on foggy and snowy days, they love it!

Now adding water injection ALONE does absolute wonders from them! Add alcohols, usually meth "not crack " and it's gas on.. I've wanted to do mine for ages, yup, even on a 300'''+klm motor! Good way of keeping the "already" cracks in the head from opening up more, "I say"

 

[tweak'e]

Exactly. Diesels with a charge air cooler make more power because they were designed & manufactured with it. Slightly denser air charge across the range and slightly more fuel injected....from the design.
Adding the cooler to a non-cooled engine (and changing nothing else) will have a pretty negligible effect unless the control systems can recognise the difference.
But adding the cooler primarily as a 'broken turbo strainer' has merit

it can be a lot more than "negligible effect".
my old toyo had a sizeable change (mechanical injection) most likely because they are old 2 valve cylinders that flow poorly and the small amount extra makes a noticeable difference. plus the change in fuel ignition changes its characteristics (due to higher effective compression).
not to mention reduction in egt's and water temps.
its the best thing you can do to a turbo diesel even if you don't add more fuel.

 

[tweak'e]

If in doubt, water meth inject that baby and floor it! Flooded or not life begins at 3000rpm !

Yup,,performance, better burning fuel, more efficient, better economy under continuous speeds revs etc. Cooler air, more oxygen dense,, they say.. Thats why i love driving mine in the mountains on foggy and snowy days, they love it!

Now adding water injection ALONE does absolute wonders from them! Add alcohols, usually meth "not crack " and it's gas on.. I've wanted to do mine for ages, yup, even on a 300'''+klm motor! Good way of keeping the "already" cracks in the head from opening up more, "I say"

yes, it works very well. (tho i don't have mine running at the mo). very good for cleaning out the engine and intake pipes.
downside is they drink the water almost as much as they drink diesel. which means big tank and can go through lots of alcohol.
one project i didn't get to finish was to run a still and make my own alcohol in bulk as i had access to free waste sugar.

 

[Been a while]

yes, it works very well. (tho i don't have mine running at the mo). very good for cleaning out the engine and intake pipes.
downside is they drink the water almost as much as they drink diesel. which means big tank and can go through lots of alcohol.
one project i didn't get to finish was to run a still and make my own alcohol in bulk as i had access to free waste sugar.

Yes, exactly, my thoughts also start up a moonshine hut! for sure!
No *****, I was talking to a mate about this months ago! Diesel too, use the cooking oil from the local fish'n'chip shop

I will do it eventually, i need a new cover for the ute tray first ... Every time I get close to doing it,,, something comes up $$ and puts it on the back burner..

 

[alfric]

So… after a few false starts with workshops that seemed disinterested I finally found a mechanic, recommended by a work colleague. Turbo inspected, bearings good, blades good, no oil leaking, slightly less sharp on the front edges, hence a slightly different sound (which is what I had noticed), inlet manifolds had a thin layer of soot which was cleaned off, leaky seals on the egr system so new seals/gaskets on the egr pipes/valve, leaky turbo seals so new high temp pipes/seals on the turbo tubes oil pressure good, timing good, vacuum tubes now all good, injectors completely stuffed, different air fuel mix in each cylinder, injector seals shot, fuel leaking into cylinder past the injectors, so new injectors and seals. Mechanic picked up overfueling issue by listening to start-up and idle ( I’d noticed a tapping/pinging sound and was curious). No error codes, engine reported to be in very good condition otherwise. Price was very reasonable, injectors charged to me at $189 each. Was told I would hear the turbo start to fail very clearly, blades hitting the housing or shot bearing etc. All good. Still got the old VP44 pump but it may never fail, and I’ll know what it is if it does go now, so all good. Engine now sounds like it did 8 years ago. Very happy.

 

[Erick]

As any diesel motor will if it’s driven and serviced correctly. Congrats tho on spending the money where it counts. . If u want a ‘ performance’ diesel go buy a ranger or whatever and all that comes with that.