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Discussion Starter · #1 ·
UPDATED January 2013

Useful related forum links:
Differences between the DCi 112 and 136 engines
DCi Buyers Guide Things to look out for Weaknesses

This thread is here to aid and provide you with information on how to best tune your engine, but it might also be of use to anyone wanting to simply learn more about the engine. Please take special note of the turbo section as it tells you about the faults and weaknesses of the turbo and how you might be able to go about preventing future turbo failure (a common problem of the 2.2 DCi engine across the board).

Based on my research of diesel tuning and information from other forums here are some things that can be done to get the best out of the YD22DDTi (Nissan 2.2 DCi).
Some of these I've applied to my car, the rest are work/research in progress. I will also link to posts as and when I know the finer details i.e. the exact pipes and IC needed for that upgrade.

For handling upgrades on the N16 please look elsewhere in the forums as they apply to all models.

General Maintenance
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Engine Oil information - http://www.almeraownersclub.com/threads/2-2-dci-oil-info.39165

ECU & Fuel Pump Reset Procedure - http://www.almeraownersclub.com/threads/reset-fuel-pump-n16-dci.46047/

Common Problems and Troubleshooting - http://www.almeraownersclub.com/threads/2-2-dci-common-problems-troubleshooting.47023/

Threads of interest -
http://www.npoc.co.uk/forum/forum_posts.asp?TID=44275&title=nissan-primera-p12-lack-of-power
http://www.npoc.co.uk/forum/forum_p...tle=nissan-primera-p12-fuel-pressure-problems
http://www.almeraownersclub.com/threads/39340-Almera-2.2-Di-SE-quot-intermitant-loss-of-power-quot

Known Fuel Pump Problems / Power Loss
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Symptoms - Lack of power, P0089 fault code.
Cause is often the SCV Suction Control Valve and might need to be replaced, along with a pump relearn done at a Nissan dealer (or use the ECU and pump reset procedure here for free!). Try the reset first as this might be enough to fix it without buying a new SCV. However we know that the SCV has been updated by Nissan since car manufacture (part no NA6860AW42B), so for peace of mind you may want to replace it anyway.

Related links
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How To Replace SCV - http://www.npoc.co.uk/forum/forum_posts.asp?TID=63206

http://www.npoc.co.uk/forum/forum_posts.asp?TID=44275&title=nissan-primera-p12-lack-of-power

http://www.npoc.co.uk/forum/forum_p...tle=nissan-primera-p12-fuel-pressure-problems

Turbo Issues, and Why They Fail
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As with anything, good maintenance is key. Regular oil changes and decent oil will help prolong turbo life. Also allow the turbo to spool down after a run (once stopped allow the engine to run for a minute or so before switching off wherever possible). Don't rev the car hard on a cold engine; allow the oil to get up to temperature.

The stock Garrett GT1849V 727477s were built with flaws, not helped by Nissan's mapping/boost sensor. Here's a bit of background to help explain those flaws. VNT controls boost pressure unlike a wastegate without VNT (like the GT1549 in the Di). It's designed to reduce lag and produce more boost at low RPM. The vanes are adjusted via an actuator that is controlled by the ECU.

More angle, more exhaust flow onto the vanes, more boost. As the revs increase the turbo goes into overboost, which is detected by the ECU, and moves the vanes to a more shallow angle to prevent the boost from climbing.

So, the problem was that the turbo did not come back from overboost quick enough. The ECU's original mapping and/or poor boost sensor caused this (both changed in a recall). This together with the turbo being built with too thin a turbine shaft led to turbo failing. The turbo overspeeds for too long causing wear on the bearings and warping the shaft. The vanes can then catch the side of the housing. For some reason only one peice of a vane tends to come off on impact, but if that peice collides with anything else, you see catastrophic failure.

Newer parts have replaced the thin shaft so if your turbo is reconditioned then it's likely the shaft has been replaced. If the car has had the recall work done as well then it's unlikely to be a problem. Earlier 727477-2 models VNT could be set via a screw which probably didnt help the overspeeding problems. Later -5 versions did not have this screw and were set at factory. I've seen reference to new turbos being -6.

The best way in my opinion to make the turbo stronger and more reliable is to make it a hybrid turbo. More reliable in a stock engine, and withstand the extra tolerances of providing more boost that's required to get a good deal more power out of the YD22 engine.

Turbo Technics can supply hybrid turbos and can be trusted with VNT too - What's a Hybrid Turbo?

Turbo Tuning
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-Hybrid from stock (see below for more details). 360 degree bearings, cut back vanes for better flow, machining of housing to fit larger compressor wheel. Making a GT1852V or GT1856V. Turbo Technics £550.
-Larger VNT turbo. A GT2256V is an option and the sized used in a VW Touareg and the Navara. Modification likely to be needed to fit manifold/exhaust/intake. However an earlier Navara (D22) turbo might fit directly to the exhaust manifold reducing the amount of custom work needed.

Hybrid Turbo
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Most of us know about the short falls of the Garrett 727477 turbo. With these problems you would be less inclined to run more boost through it. It seems even on a standard map they are likely to blow up with Primeras, X-Trails and Almeras alike sometimes going through a turbo every year!

A Hybrid Turbo is designed to be stronger and more efficient. Bigger bearings and a super accurately balanced shaft and turbine/compressor wheel allow the turbo to operate reliably, and cut back vanes with a machined housing improve gas flow.

Give this treatment to a GT1849V 727477 and you're on to a winner. Turbo Technics are the people to take this on and they do a superb job at that. The unit is a direct fit as the exterior of the housing isnt changed in any way. Whether you're tuning your DCi or simply looking for a more reliable solution and/or a replacement turbo I can't recommend this product highly enough. Don't buy twice with a refurbished standard unit or even a new one from Nissan.

After the turbo is fitted you'll notice and improvement in drive. The turbo is much more responsive and gives a more confident feel even from 1000rpm, and you'll find MPG improved all round, especially on longer runs.

Part Number: TT 727477-5SP
Fitment: Direct fit, no modifications required.
Cost: £550

Tel: 01604 705050
http://www.turbotechnics.com/





When fitting a new turbo it's recommended that you replace the relevant gaskets and studs/nuts. A turbo fitting kit is available from Nissan for about £35.

Clutch
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At present there's no aftermarket clutch made for the YD22.

It's possible that the QR25 and QR30 in the US uses the same gearbox (casing but imagine different ratios). There are uprated clutches for these. Torque is the killer though and even though the QR30 produces over 200bhp stock the torque won't be anything near that of the diesel unless it's turbo'd. My point is that you're going to have to buy a pretty hefty clutch which will be expensive, and with shipping costs and customs charges on top... a custom one made localy could even end up being cheaper. ...

Exedy make an OEM spec clutch and I've emailed them to ask if they can take that and uprate it. Nothing yet but watch this space.

Here's some specs on the standard clutch from Exedy's website, and what else those parts are used in (interesting the to see the Skyline has the same clutch cover which means it's got to be quite strong already):



Transmission/Gearbox
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The YD22 136 has a 6 speed manual RS6F51R gearbox. It comes with an open differential. With more torque and power you're going to start spinning up the wheel that has least traction. Powering out of corners means the inside wheel or off the link probably means the passenger wheel. To even out the power a limited slip diff is used or LSD. In Europe we have no such option.

In the US the RS6F51 transmission is used in the A33 Maxima with the VQ30 engine, and B15 Sentra SE-R SpecV with the QR25 engine, albeit with different ratios (different mounting points in the bay). The SpecV comes with a Helical LSD which uses gears (RS6F51H). Other types are viscous (VLSD) and are used in the Maxima (RS6F51V), and also the A33 Maxima comes with a non-LSD type just like the DCi's here, labelled the RS6F51A.

Helical = gear driven, holds under harsh conditions, engages instantly
Viscous = fluid driven, overheats when pushed hard, takes a while to engage

A recent revelation tells me that the differentials in the A33's Maxima 6sp, and in fact the whole transmission are near as damn it identical. The diagrams directly below this paragraph show the cross sections as the same. Knowing that the B15 SpecV HLSD diff drops into the A33 means dropping one into the DCi's RS6F51R should be no trouble either.



Differential Close-Ups

N16 RS6F51R


A33 RS6F51A


B15 RS6F51H


Reference: Maxima 5 gen LSD work - http://forums.maxima.org/5th-generation-maxima-2000-2003/578877-6th-gen-transmission.html

http://www.nissanclub.com/forums/en...006/282665-screw-lsd-tranny-swap-painful.html

YD22 DCi__________________________________QR25 SpecV




YD22 DCi Open Diff


QR25 SpeV Open Diff


QR25 SepcV HSLD


The thing to do now would be to import a B15 SpecV tranny and go from there.

EGR Valve
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Exhaust gas recirculation is used to keep emissions in check. It forces exhaust gas back into the inlet manifold where any unburnt fuel is recombusted, and reduce any NOX gases being expelled to atmos. It is also supposed to help keep exhaust temps down. The problem is that all the soot and unburnt waste that is inherently expelled by Diesel engines ends up getting stuck all round the inlet manifold. After a short while even, this can lead to a completely clogged up inlet, and reduced performance. I'm going to take a day and take apart the EGR system and inlet manifold and get it cleaned up.

Blanking off EGRs is common and will mean you won't get clogged inlet manifold again in the future. Many have praised the effects of blanking it off. Because it is supposed to reduce gas temps it's a good idea to monitor these temps with an EGT gauge. You'd need to get a thread tapped into the exhaust (easier if you've got a custom one and have removed the CAT coming off the turbo). I'm going to contact Nissan and ask for nominal exhaust gas temps and will post them up so we know what to aim for and what level to set a warning if your gauge can do so.

Known Fuel Pump Problems
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Symptons - Lack of power, P0089 fault code.
Cause is often the SCV Suction Control Valve and might need to be replaced, along with a pump relearn done at a Nissan dealer (or use the ECU and pump reset procedure below!). Try the reset first as this might be enough to fix it without buying a new SCV.

Related links:
http://www.npoc.co.uk/forum/forum_posts.asp?TID=44275&title=nissan-primera-p12-lack-of-power

http://www.npoc.co.uk/forum/forum_p...tle=nissan-primera-p12-fuel-pressure-problems

ECU & Fuel Pump Reset Procedure
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Found an ECU & Pump reset procedure a while back for the Nissan Navara on their owners club forums. It recently came up that a reset needed to be done on a 2.2 DCi P12 Primera, but Nissan wanted £90... So I posted the link to the nav forums on the off chance it might work. I know that the ECUs have the same Pin outs so very similar if not identical, so it was worth a shot.

It worked! So it's safe to assume it'll work on the N16 Almera too.

Source: nissan-navara.net

http://www.nissan-navara.net/viewtopic.php?f=15&t=5786

Thanks to Boohoo for reading through the workshop manual, resetting ECU and FUEL pump MAY help in cutting down on that horrible tapping noise that the D40 suffers from.
Ive carryed out this reset and the engine is alot smoother, more responsive, less smokey and alot less tappy.

To carry out the reset carry out the following

Turn ingnition on so all dash lights come on.

Wait 3 seconds

PUMP accelerator pedel 5 times within 5 seconds....

with foot now OFF accelerator wait 7 seconds...

After 7 seconds press and hold down accelerator pedel for 10 seconds...

Atfer 10 seconds the Engine Managment Light will start to flash, at this point remove foot from accelerator.

the Nav is now in diag mode, so let the EML flash for a bit. the press and hold the acclerator pedel down for more than 10 seconds..this will then reset ECU and fuel pump etc......and put them into learning mode.

NOTE: When the EML light is flashing, this is listing possible fault codes... so if you know how to read the fault codes or know the sequences then you can figure out any possible faults with your Nav with out getting the dealer to do it!!
Long overdue re-write and update of info. Could a mod / admin please copy and paste this over the top of what's in the first post please? :)

Long overdue re-write and update of info.

UPDATED January 2013

Useful related forum links:
Difference between DCi 112 and 136 engines in the N16
DCi Buyers Guide Things to look out for Weaknesses

General Maintenance
----------------------------------------------------------
Engine Oil information -
http://www.almeraownersclub.com/threads/39165-N16-DCi-Diesel-Engine-Oil-Change-Info

Threads of interest -
http://www.npoc.co.uk/forum/forum_posts.asp?TID=44275&title=nissan-primera-p12-lack-of-power
http://www.npoc.co.uk/forum/forum_p...tle=nissan-primera-p12-fuel-pressure-problems
http://www.almeraownersclub.com/threads/39340-Almera-2.2-Di-SE-quot-intermitant-loss-of-power-quot
 

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thanks for that a really useful in depth post. have bookmarked for further use found the info on the turbo especially useful as like most diesel owners this is the bit most on my mind.
cheers :thumbs: :bow:
 

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Discussion Starter · #6 ·
They do standard clutches but I was really looking into an uprated clutch you see. I have to say though so far the standard Nissan clutch has been solid, even with the torque I'm running now.

Just had a look again and the part number for the clutch disc is different to that of the Almera on the Exedy website. It's the same one used in the 200sx, so I wonder if the X-Trail has a tougher spec disc. Would make sense as it's designed to tow. Pressure plate is the same though and that seems to provide a good clamping force to even hold 320lbft at 2200rpm! ;)
 

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Discussion Starter · #7 ·
Added a section on transmission.

Use this picture of the X-Trail's YD22 6sp for reference. The only difference to the pictures above is the mounting for the transfer box :)

 

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Great post, excellent information and research, wish I had read this earlier.

I did the ECU and fuel pump reset and relearn as I suspected there was an issue with it. I took a video of the EML flashing the error codes.


Eoin
 

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Bearing in mind the raft of various veiws of whether it is good to blank of the EGR or not what have your experinces been ? The two schools of thought being give the EGR a clean, it reduces NOX, etc and the blank it off route which stops the cokeing problem and while not helping NOX issue means the engine works better, but the ECU has a kitten fit. Is it worth doing on the Nissan engine ?
 

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Discussion Starter · #15 ·
Mpg is better with EGR off as is response I have found. As I said I have just unplugged the solinoid rather than blank it, as it does the same job but less of a faff come MOT so that there is light on.
 

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Hi EDK, sorry being a bit dense here, so you have not blanked off the EGR just unplugged it so the valve remains shut, cunning :biggrin: If I understand correctly you are not getting a MIL light but it is throwing up an error code ? I take it you are getting no black stuff from the exhaust, which confirms the EGR is the issue ?
 

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Well I did a bit of an experiment and unplugged the Xy for the weekend (hot engine). No error code, or MIL, and to me there appeared to more emmissions, smoke, on pushing the gas pedal with the EGR disconnected, interesting and unexpected result. So I think the EGR may need further inspection, spanners :headbang:
 

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Thanks EDK - I plugged in Nissan DataScan II and did not pick an error code either. I also plugged in CGP and it reported no errors either. I assume that the EGR being unplugged as you suggested earlier means it stays shut, which would indicate it may be time to reset the ECU and if that does not work, would in turn mean the injectors would be suspect if smoke continues on heavy throttle !
 
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