Diesel Care

Learning to Love your Common Rail Diesel

A guide to correct operation, maintenance, performance modifications and ultimately cost

savings.

Tom Hewitson 2019

V4

With 45 years of experience and knowledge in Recreational, Trade & Mining, the GO 4×4 team are the ‘GO-to’ for all 4WD Products, Services & Advice.

Learning to Love your CRD – Common Rail Diesel

Remember 2 things, it’s all about emissions (for 5 years) and prevention is the best cure. The following is primarily a discussion around how to increase the longevity of CRD engines and an

introduction to Performance Enhancements. 1 It’s ALL about emissions! All manufacturers are striving to improve fuel economy, as this reduces emissions, they use lighter weight oils (even zero weight engine oil is now available), so when the crankshaft splashes through the sump oil there is less drag, they use lighter construction materials – to reduce weight to reduce fuel useage to reduce emissions, they even change alternators to the new Variable Output type that reduce the drag of the brushes by reducing the charge voltage. (This type of alternator necessitated the development of DC to DC Auxillary Battery Isolator/Charger systems) It’s ALL about emissions. Importantly, once a vehicle is 5 years old, its emissions no longer count in the calculation of any nations total emissions output! Hence, engine manufacturers have developed emission systems to keep the engine compliant for 5 years, which in Australia works out to around 150,000kms. Beyond 5 years, the emissions don’t count, (and in many countries there a very few cars 5 years old or older), so there is little interest in the years beyond. However, in Australia, the average vehicle age is over 10 years. At this point (and sometimes a lot earlier if a vehicle does a lot of short runs), the detrimental effects of poorly engineered emission systems can lead to expensive repairs and maintenance – cracked heads, cracked and worn pistons, blown out head gaskets, a lot of labour time, chemicals and parts are consumed in the process of restoring good health to these engines. But more about this later. At GO 4x4 we are often called upon to diagnose issues with CRD engines and rectify the problem. NOTE: If you are unfamiliar with any terms, please refer to the last page. 2 What is CRD – Common Rail Diesel? Common Rail Diesel was a huge advancement in diesel technology (using very high injection pressures and electronic injectors controlled by an ECU), that CRD was released from around 2006/7. It provides substantially more power combined with significantly improved economy, engines are quieter and have less emissions compared to previous generations of diesel engines. The best of all worlds, you would think! Who could ask for more? However, along with these advancements can be expensive reliability issues - compared to earlier generations - so it is important that owners maintain & operate their CRD correctly. In concert with minor modifications, you can reap all the rewards these engines can provide over a lifetime of use.

3 How CRD Works CRD has a high pressure fuel pump which delivers diesel up to the Common Rail, a feed tank or reservoir that holds pressurised fuel waiting for the injectors to open. There is a pressure sensitive return valve at the end of the ‘rail’, holding the fuel pressure, stopping it bleeding off on its return to the fuel tank. The injectors are electronically controlled by the ECU, and based on the readings from various sensors around the engine, - MAS, MAP, Crank Angle, TPS, EGR, Boost, Cam Timing, Injector Timing and Pressure, air temperature, throttle position, etc, - the computer pulses the injectors to release fuel into the cylinder, (according to the program ‘map’ of response for that set of circumstance (and it is this map that is modified with a Custom ECU Re-map - but I digress) often many times per stroke (up to 10), so that as air is drawn into the cylinder (as the piston moves away from the head), a small amount of fuel is atomised to match the air volume (so that in theory all the fuel is burnt and extinguished by that air, hence, you guessed it, less emissions!) All the fuel is used to create power and is not lost down the exhaust pipe, resulting in the black exhaust smoke often seen in older engines or engines under load. The excess fuel delivered to the ‘rail’ is returned via a fuel cooler to the fuel tank, and the cycle repeats. Fig2 Common Rail Diesels rely on fuel pressures being 10x the pressure of earlier engines, greater than 22000psi as compared to around 2000psi. This is the reason for the fuel cooler, often found bolted to the underside of the vehicle – and needs to be protected in many off-road circumstances.

Fig1 Consider Under vehicle Protection Plates (Bash Plates) to protect the underbody fuel cooler. As you see, this one has been beaten-up.

The CRD injector may open-close a billion times during its service life, fuel is being forced through the injector at 2000kms/hour in bursts of 1 or 2 milliseconds, where the clearances are 30 times smaller than a human hair. They’re incredible devices! See Section 7 for preventative maintenance issues.

Fig2 The high fuel pressure, the precision injection controlled by the ECU, all lead to cleaner, quieter and more powerful engines. Then comes the Emission Systems. 4 Crankcase Pressure or Blow-By All engines since around the mid-1970’s have had the piston ring ‘blow by’ redirected back into the engine, via a tube connecting the tappet cover to the air intake, usually between the air-cleaner and the turbo. On the ‘suction side’. ‘Blow-By’ is normal. Even from new, there is always some combustion and turbo boost pressure lost past the piston rings into the sump and the internal cavity of the engine. The air intake draws this gas into combustion, along with a small amount of oil mist or fumes carried by the gas flow. As the engine wears, or more specifically as the rings and bore wears, there is greater gas flow and hence greater oil fumes. CRD engines have boost pressures that are 50% or more higher than earlier engines, so increased blow-by is observed earlier in an engines life compared to older style engines. Hence oil fume volume is greater. These oil fumes coat the inside of the intake duct work (sometimes leaking externally at duct joins), coats the inside the turbo, inside the intercooler surfaces - reducing its cooling efficiency and most importantly, it burns inside the inlet manifold leaving significant deposits. The deposits reduce air volume, reduce performance, reduce efficiency, hence increase emissions. The oil burns inside the manifold due to the hot exhaust gases being released into the manifold via the EGR (see Section 5 & 6), as well as the proximity to the hot engine itself. A well designed baffled and filtered Catch Can is recommended to alleviate this problem. The Catch Can is fitted along the pipe work from the tappet cover to the air intake. The oil fumes are extracted by the Catch Can Filter but the gas flow is uninterrupted. Fig3 The Catch Can also extends the service life of DPF’s, due to the excessive oil deposits not being burnt in the engine, hence not blocking the DPF. See Section 7.

GO 4x4 Recommends the Provent Catch Can. The Provent Catch Can does not require disassembly to drain, has a relief valve that regulates crankcase pressure variations on hard acceleration vs rapid deceleration, and a by-pass valve to relieve pressure if the filter is kept beyond its service life. Provent Catch Cans also come with a comprehensive kit and easy mounting bracket. Fig3

5 EGR - Exhaust Gas Recirculation In 2003, EGR valves were introduced to diesel engines in Australia. In a bid to reduce emissions, burnt exhaust gases are recycled back into the engine, via the inlet manifold and the EGR valve. This valve is controlled by the ECU, and it opens in circumstances where the ECU determines there is an opportunity to reduce emissions. Remember, it’s ALL about emissions. Typically emissions are greatest with slow running, short trips, low engine temperatures, excessive idling. So, in these circumstances the ECU will try to contain the worst of the emissions by opening the EGR valve, re-burning the smoke and particulates. However, this is the problem, unburnt fuel and particulates etc are being fed back into the inlet manifold, and form restrictive deposits. 6 Compounding Emission Systems Failure The oil fumes from piston ring blow-by combine with the sooty diesel exhaust gases being fed into the inlet manifold by the EGR valve. The EGR is usually located on the inlet manifold and there are several points that follow:

1. The thick black paste of particulates mixed with oil build up in the manifold, in the head ports, on the valve stems and valve seals.

2. The thick black paste bakes into a very hard ‘scale’ the closer it deposits to the engine. 3. The flow of gases is never evenly spread across all cylinders.

The thick paste from Point 1, the EGR valve can be physically restricted, either ‘gummed’ up and jammed shut, leading to an engine warning engine light. Alternatively, it can be jammed partly or fully opened. EGR valves can jam open or shut with the mix of particulates occurring right at the valve.

If jammed open, significant volumes of hot exhaust gases flow into the inlet manifold. The engine will choke until turbo boost pressure is great enough to push the exhaust gases back into the exhaust pipe and it can get some normal air. (usually around 2000rpm). On Ranger and BT50 it can lead to the plastic inlet manifold melting! Jammed open or partly open will always lead to reduced performance and reduced fuel economy, hence greater emissions. Imagine the circumstance where an EGR feeds into just 2 cylinders, and with the particulate matter and oil build up, it slowly restricts airflow into those 2 cylinders. Fig4 The build-up is unknown to the ECU which monitors the incoming airflow at the air-cleaner. Assuming an even distribution of air to all cylinders, it delivers fuel with an even distribution. The reduced airflow into those 2 cylinders leads to increased combustion temperatures, not due to over fueling, but due to ‘under airing’. This can result in piston failure due to excessive temperatures. This is the exact circumstance that occurs with the Nissan ZD30 engine (4 cylinder 3.0Li TDI in the GU Patrol, Navara D22), often referred to as the Nissan ‘hand grenade’ - engine failures are so common. The ZD30 is a standout example of poor design, but take no comfort, I have not observed any manufacturers intake system where the particulate matter and oil buildup is evenly distributed across all cylinders. Prevention is the ONLY sensible option for longevity. Fit a baffled filtered Catch Can.

Fig 4. Typical Examples of restricted EGR Valves and uneven distribution.

EGR Valve control and regular maintenance. EGR Maintenance There are a variety of chemical cleaners that can be released into the intake system, to breakdown the built-up deposits. GO 4x4 uses the Wynns EGR4, a workshop grade cleaner that is applied directly to the manifold surface, not just a simple ‘spray in the air-cleaner’ gimmick. A chemical clean cost is typically $150 to $200. If the buildup is significant or of some age, it may be necessary to remove the inlet manifold and duct work to physically remove the deposits. Sometimes the ‘scale’ deposits have to be chiseled off, they are that hard. We have not seen any chemical cleaner that will successfully remove the hard ‘scale’ deposits found closer to the engine. This can be time consuming and costs of around $800 to $1200 would not be unexpected.

Clearly prevention is the best option. EGR Alternatives Other alternatives are the fitting of EGR blocking or limiting plates.(Fig5) These are a stainless steel plate that physically fits between the EGR valve and the manifold. The complete block is suitable for earlier systems, but later engines have EGR flow sensors, which fault when no exhaust gas flow is detected through the EGR. These are a simple fix, costing under $20 and take an hour or so to fit. Ask GO 4x4 for a specific price for your application. Fig5

EGR plates come in a variety of shapes and sizes to suit each application. Alternatively the ECU mapping can be altered so that the EGR valve remains closed at all times. This is usually done in conjunction with a Performance Re-Map, cost is typically from $1000 to $1600, depending on make, model, year etc. (see section 10 for more detail)

Any alteration of the emission system may not comply with emission standards for on-road use. Note: The EGR valve will not open when the turbo is boosting. If it did, turbo boost pressure would be lost down the exhaust pipe, bypassing the combustion chamber. This results in fuel not being combusted due to the lack of air. Vehicles driven harder and for longer tend to have less EGR issues. 7 DPF - Diesel Particulate Filter DPF is standard on all Euro5 spec vehicles, in Australia all diesels from October 2016-on. They are also fitted to some models before this period, usually in combination with automatic transmissions – eg Pajero 2008-2010 Auto, Navara D40 Auto, Pathfinder R51 Auto, plus others. The DPF device is fitted in the exhaust, typically directly after the turbocharger. Fig6 It captures diesel exhaust particulates or soot from the exhaust, and modifies them into harmless products in a burn-out process called regeneration. DPF’s have pressure and temperature sensors at both ends of the filter, and by monitoring the differences between these sensors the ECU manages regeneration. The volume of particulates generated and captured varies tremendously, and is dependent on such conditions as; engine load, throttle position relative to gear selected, fuel quality, EGR operation, injector condition, engine condition and tune, appropriateness of engine oil used and condition, to mention a few.

Fig6 New DPF and a blocked DPF. There are 3 styles of Regeneration: Passive, Active, Forced. Passive Regeneration Passive Regeneration occurs when the engine temperature is at least 500C for at least an hour. In this circumstance, the particles are converted to CO2 and very small amounts of fine ash which remain trapped in the DPF. On shorter trips, or at lower temperatures, or start/stop driving, the DPF will accumulate the ‘blocking’ particulates without doing a regeneration. Eventually a regeneration will be required. Fig7 Active Regeneration This occurs when the ECU actively lifts the combustion temperature to do the burn-out. Manufacturers have different methods of doing this, but they are based on increasing combustion temperatures ie having 1 or more injectors stay open longer to create a higher combustion temperature – hence higher exhaust temperature, or having an injector open when the exhaust valve is open so that raw fuel enters the exhaust creating extra heat, or the ECU may change timing or have an extra injector that is only used for regeneration purposes. Often the driver is only aware of the active regeneration when excessive smoke is seen from the exhaust. It’s not for long, maybe only 15 minutes. If the process is interrupted, ie by turning off the engine, slowing down, idling for a period, the ECU will attempt to re-engage the regeneration on several occasions. If it is unsuccessful, the warning light will illuminate. The vehicle will then need to be driven to achieve a passive regeneration or move to a manual regeneration. Otherwise it is danger of going into a ‘hard limp mode’. Once in a ‘hard limp mode’, a high end scan tool will be required to reset the ECU. Taking the negative terminal off the battery for a few minutes will work on a ‘soft limp mode’ setting, but not on the ‘hard’. ‘Hard limp’ mode is typically 25km/hr top speed, possibly trapped in 1 gear. Not very convenient! Forced Regeneration Forced or manual regenerations are performed by a switch on the dash of some models, ie 70 Series Landcruiser, or at a specialised workshop. A high end Scan Tool will be needed to interrogate the ECU and Request a Regeneration. If this is not successful, a new DPF may need to be fitted, cost range from $2000 to $8000 plus fitting. Even with fitting a new DPF, the ECU needs to be ‘told’ this is the case, otherwise it will continue pursuing the regeneration options!

An alternative is to remove one of the sensors from the DPF and spray a chemical cleaner directly into the DPF, in the hope this unblocks the exhaust enough to either drive it into a Passive Regeneration or Force a Manual Regeneration. Fig7

You are probably thinking this is all very troublesome, but these are the negative aspects of the late model CRD engine. Pumping raw fuel into the exhaust, lifting combustion temperatures so high, it is hard to believe these actions bring longevity to an engine or its surrounding components. Fig7 Remember, it’s ALL about emissions. For 5 years. Hence, ECU Re-Mapping is often chosen as a way of eliminating the whole DPF set of issues forever, along with a substantial increase in torque, power and fuel economy.

Another option is to remove the DPF, but this may not comply with emission standards for on-road use. See section 10 for more detail or ask GO 4x4 for a specific price for your application. 8 Auxiliary Fuel Filters Referring to Section 3 above, fuel pressures and component tolerances, it is of little wonder that 4x4 owners are always advised to fit an additional fuel filter or Pre-Fuel Filter. However, this is a misnomer. The standard CRD fuel filter is filtering down to 1 or 2 microns and the ‘pre-filters’ are usually 30 micron. They are a basic ‘rock stopper’! Little else. Their principle role is one of ‘Water Trap’. Fig8 BTW, if you fit an additional fuel filter which is also 1, 2 or even 10 microns to a CRD, it is common to have the ‘Engine Warning Light’ illuminate in circumstances of high fuel demand. There is too much restriction or drag. The 30 micron will not do any filtering, but it is not needed anyway, it is the water in the fuel that will lead to the expensive component failures. The system is lubricated by oil, diesel oil, diesel is an oil, not a solvent like petrol. If water displaces diesel in an injector, the internal components wear rapidly with no lubrication. Remember the fine tolerances, 30 times less than a human hair! Injectors of previous era engines, say 1HZ Toyota (1990 to 2006) cost around $80 per injector and take 2 hours to fit. $600 to $700 will see a set fitted. CRD injectors are commonly $400 each, and by the time the associated seals and gaskets are changed with the injectors, even a 4 cylinder Hilux (1KD-FTV, 2005 to 2015) may cost $2500 to change injectors. On a V8 4.5Li TDI Landcruiser, (1VD-FTV 2007-on), that could blow out to $4000 or $5000!

So, it’s definitely worth investing in the misnomer - additional fuel filter, Pre-Filter or more correctly termed, Water Trap. Fig8 Auxiliary Fuel Filter

GO 4x4 recommends fitting the additional fuel filter AFTER the OE filter. The philosophy is that with the high volume of fuel passing through the CRD system, (the fuel is being used as a coolant) it is almost certain that should the Filter Warning Light illuminate, water will have passed further into the injection system. Even the most diligent driver is unlikely to observe water accumulating before the warning light illuminates, as the volume of fuel being delivered to the ‘common rail’ is far greater than the volume actually being used. ie for the 4.5Li TDi Landcruiser engine, 1VD-FTV, the pump is returning 400ml/minute or 50ml/7.5 seconds of diesel to the tank after the engine has drawn its useage. The Auxiliary Fuel Filter-Water Trap capacity is 50ml, so in theory the water trap could fill every 7.5 seconds. Not much use when you are on an 8 hour drive, during which time 190Li of returned fuel, plus the 96Li of used fuel (at only 12Li/100kms), a total of approximately 300Li has passed through the fuel and filter system, during just one 8 hour day. If the water trap is fitted pre-OE filter, even if you check it every morning, it’s not often enough! If the Water Trap is fitted after-OE filter, then there is an extra accumulation point after the light sensor, so there is a good chance water will NOT have passed further into the fuel system. In addition, the auxiliary fuel filter elements are hydrophobic, they resist water flowing through them. The other point to note is that you don’t have to be a remote outback adventurer using old jerry cans to have water in your fuel tank. Water is continually accumulating via condensation from the air that is drawn in to replace the fuel used by the engine. In humid conditions, (especially up north) the amount of water vapour is much greater, and even opening the fuel cap on rainy days at the fuel station will allow moist air into the tank. Cooler temperatures ie overnight , result in the vapour condensing to liquid and running to the bottom of the tank, accumulating below the diesel (diesel is an oil that floats on the water), so the water is often the first liquid to be drawn up to the engine. A fuel contamination issue also arises from this condensation, the diesel fuel algae that lives at the fuel-water meniscus, feeding on the diesel, but living in the water or on the exposed surfaces of the tank. The live bacterial growth can be a problem if drawn into the filtration system, but it’s the dead

algal matter that accumulates on the bottom of the tank and is commonly drawn in, causing blocked filters, pump and injector damage. A biocide treatment should be used on a regular basis to control these bacteria, particularly in the tropics.

Fig9 Bacterial growth found in a fuel filter.

GO 4x4 uses the Fuel Manager Water Trap Filter system, and configures them post OE filter. Cost is typically under $500 fitted, so clearly it is economical insurance against water ingress into the injection system of CRD engines. Ask GO 4x4 for a specific price for your application. 9 Diesel Injectors There are 2 primary styles of injectors in CRD. Fig10 Solenoid type, have an electronic solenoid at the top of the injector. The solenoid is switched by the ECU sending a voltage pulse to the solenoid to open them. It can have many openings per injection cycle.

Fig10 Typical Solenoid and Piezo Injectors Piezo Type, use piezoelectric technology to open and close the injector at extremely high speeds and precision, with improved performance and efficiency over solenoid types. When power is applied to piezo crystals they expand, they return to their original size as soon as the

electric current is cut off. The expansion of one crystal is too small to see with the naked eye, so several hundred little piezo crystals are placed one above the other covering a more than half the length of the injector. When current passes through these hundreds of crystals their combined expansion is enough to open the injector. The crystals expand downwards and an upward movement is required to open the injector, so two very small levers are used to reverse the process and open the injector and a spring closes it as the crystals contract. Because of their operation, piezo injectors can open and close much faster than mechanical injectors, hence allow more precision in the injection process. The ECU is monitoring the fuel requirement to the milli-second, so piezo type also inject several times per injection cycle. Just the right amount of fuel can be used at just the right time, so little or no fuel is wasted. Piezo type is more efficient and more durable than solenoid type. Injector wear in CRD engines (usually from water issues, Section 8 above), is measured by reading individual ‘feed back’ values of each injector, with a high end scan tool. The ’feedback value’ is a measure of volume of diesel (in cc’s). Excessive fuel leads to piston and ring failure due to excessive combustion temperatures. Feedback values upto 3cc’s are regarded as acceptable, in excess of 3cc’s is the industry standard for ‘Action Required’ immediately. At 5cc’s, it’s imminent engine failure…. Stop driving the vehicle! Fig9 Excess fuel is noticed by the casual observer in extra detonation noise, particularly when cold. As the excess fuel volume increases, the noise level increases and continues to be noticeable as the engine reaches operating temperature. 5cc’s feedback has a very noticeable noise when cold. However, noise when cold under light load, typical user description, is NOT a diagnosis of injector wear or failure. I am aware that many workshops, even specialists!, change injectors on report of noise, with no further investigation. In one case, the owner of a KUN26 Hilux 1KD-FTV, changed the injectors twice, at 2 different workshops, for a total cost of $5000 – with no change to the noise. It was never the injectors in the first place! It was a blocked inlet manifold. Fig4 The ECU knows when an injector is worn, when excessive fuel is being delivered to 1 or more cylinders. To complicate matters, the ECU then reduces the amount of diesel being injected by other injectors, to manage the balance or vibration of the engine. However, this masks the problem of over fueling to an inattentive driver. Fig9 Injector Feedback Values 1VD-FTV @ 160,000kms

It is good practice to have your service agent read the Injector Feedback Values every 50,000kms. Ask GO 4x4 to do this at your next Service to determine the wear of your current injectors.

Injector Mounting. Often CRD injectors are held into the head with a ‘crows foot’ style clamp. Fig11

This tends to pull the injector to one side, ever so slightly. In doing so, the bottom sealing washer does not seal perfectly, carbon from combustion makes it way up the side of the injector, between it and the head.

Two things flow from this problem:

1. the injector can be dammed difficult to remove, to the point they pull apart (total destruction) during extraction and

2. the same carbon makes its’ way into the engine oil, as the injector passes from the head into the tappet cover cavity, and then through the cover to outside of the engine. Oil flow carries this debris from the tappet cover cavity into the sump, where the oil is recycled into the oil pump. The problem lies in the carbon debris building up on the oil pickup screen, eventually restricting oil flow. It is not uncommon to see engine failures due to oil starvation. Catastrophic failure. Likely cost from $8000 to $15,000. GO 4x4 recommends changing the engine oil every 5000kms, and using an Engine Oil Flush with each change. The Flush breaks down the oil sludge trapped in the engine so it flows out with the used engine oil.

The crows foot style clamp is used in most 4x4 CRD engines, Landcruiser, Hilux, Ranger, Mazda, for example. It is good practice to check the oil pickup screen with every oil change interval. It is simply a matter of looking into the sump plug drain hole to observe the screen. A small amount of time spent here is a mighty lot of prevention! Another precautionary note is when tightening fuel return or drip rail pipes. On some models, eg 2007 to 2016 1VD-FTV engines this return pipe is inside the tappet cover. You cannot observe it with the engine running. If there is any amount of fuel leakage from an incorrectly fitted washer, or deformation of the rail, then leaking diesel accumulates in the engine oil. It dilutes the engine oil, the loss of viscosity can lead to premature wear of the upper mechanical components, like cam gears, timing chains and lash adjusters. I recently repaired an engine with just this problem, (1VDJ-FTV in a 76 Series, solenoid type), it cost in the vicinity of $9000 to rectify. Changing the engine oil every 5000kms in CRD vehicles is also recommended due to the above. Ask GO 4x4 to check your oil pump pickup at your next Log Book Service. Remember 2 things, It’s ALL about emissions (for 5 years) and Prevention is the best cure.

10 Performance Enhancements Power Chip Exhaust Replacement ECU Re-Mapping Plug-In Power Chips Power Chips typically increase fuel pump pressure and duration. In the end, they increase fuel delivery by one means or other to increase performance. Commonly gain 20% gain in Torque on the Standard engine. On some models, the settings can be changed to take advantage of any modifications already fitted, eg high flow exhaust, intercooler, snorkel. We recommend that you change the exhaust to a larger diameter to allow the increase of fuel and air being forced into the engine to be efficiently released, but it is not essential. Typically cost under $1000 fitted. Exhaust Replacement Complete 3.0" Mandrel bent Hi-Flow Exhaust Kit, including dump pipe, replaces the complete exhaust, from the back of the turbo to the rear bumper. This will make quite a difference to fuel economy (10%+) as the turbo spools up much earlier in the RPM range, so brings the torque on earlier - equates to improved efficiency. The turbine spins earlier due to the greater space for the hot exhaust gases to expand into. The hot gases expand as they cool (opposite of compressing them, the Law of Adiabatic). The hotter the gases (more fuel load) or the larger the space (bigger exhaust pipe, limitation is some back pressure is required) the more rapidly those gases expand. It’s the expansion of the gases that make the turbo spin, as they rush past the turbine into the greater space of the larger exhaust. For lower down torque, better towing and safer overtaking, a 3” Mandrel bent exhaust (in coated mild steel or stainless) will make a noticeable difference, but not to the same extent as a Power Chip or ECU Re-Map. ECU Re-Maps GO 4x4 specialises in CRD 4WD vehicles only, and are providing a custom user-specific tune. It is not a preset package tune from Russia or Europe (where air temperatures are vastly different to Australia), that is then downloaded into your ECU. Nor is it a "plug-in" or "solder-in" chip. It’s about getting the optimum performance for the same or less fuel with a custom re-map, setup according to your use of the vehicle. You’ll need to advise what you use the vehicle for, and what you find lacking. For example: Towing a Van occasionally, Towing a Heavy Tradie Trailer every day, carrying a Water or Fuel Tank for a Fire Unit - there are so many uses, the tunes vary substantially. The focus is drivability, widening the useful RPM range, to change the entire feel of the vehicle. To achieve this, the ECU is interrogated to change hundred’s of tune settings – the relationship of fuel, air, timing sensors (MAS, MAP, Crank Angle, TPS, EGR, Boost, Cam Timing, Injector Timing and Pressure, AFR’s) – a myriad of networking that generates the factory tune.

Result: Fig12 If you run down the graphs at the same RPM, you can see the red line is above the blue in the AFR's and all other specs: Power, Torque, Boost are up while Fuel Load is down, all the way to 2300rpm. All happening at the same time. And even when the AFR’s drop below the standard setting, it’s not by much. It’s not magic, it’s using the existing ECU and sensors, just changing how they interrelate to each other. Ask GO 4x4 for a cost for your specific application.

11 Summary

1. It’s ALL about emissions, for 5 years, not about engine longevity 2. If there are any issues, methodical DIAGNOSIS is the key 3. Change engine oil at 5000kms with an Engine Oil Flush 4. Fit an extra fuel filter Water Trap – Fuel Manager/ARB Diesel Care after the OE filter 5. Fit a baffled filtered catch can – Provent/ARB Diesel Care 6. Stop immediately if any engine light illuminates and seek advice. Call GO 4x4! 7. Drive a DPF fitted vehicle at least 30minutes continuously several times a month 8. Do not idle a CRD for extensive periods, more than 5 minutes 9. Read the Injector Feedback Values every 50,000kms to determine injector wear

Keep in mind, there is no accounting for all the emissions created during the rebuilding of engines, the replacement parts manufactured, shipped and fitted during repairs to prematurely failed late model diesel engines, OR all the chemicals used trying to clean them and keep them efficient. Let alone the cost. The engines themselves have all the latest materials and design techniques to make them very reliable, unfortunately the emission systems often cause premature wear and component failure.

Fitting a filtered baffled Catch Can, fitting an extra Water Trap Fuel Filter and being aware of the issues, maintenance and modifications surrounding the EGR and DPF devices, implementing preventative steps with a relatively small upfront cost early in the engines life will be a ‘big time saving’ over the life of the engine and make sure they go the distance. Re-Map the ECU to change settings for engine longevity. If you wish to discuss these options or seek further advice, please contact myself or one of the experienced team at GO 4x4. 08 8369 0999 or offroad@go4x4.com.au Terms ECU Electronic Control Unit - computer CRD Common Rail Diesel EGR Exhaust Gas Recirculation DPF Diesel Particulate Filter- captures diesel particulate matter from the exhaust TPS Throttle position sensor MAP Mass Air Pressure – turbo boost pressure MAF Mass Air Flow – air passing through the air cleaner CAS Crankshaft Angle Sensor SCV Suction Control Valve NOX Nitrogen Oxide Sensor O2 Oxygen Sensor CAT Catalytic Converter TDC Top Dead Centre – piston is at the top of cylinder Solenoid Injector – solenoid controls injector operation Peso Injector – has crystals that react to current to control injector operation