Copy of EDC17 Maps Guide

EDC17 Maps Guide

Drivers wish The drivers wish maps are usually grouped like in an EDC16 file. E.g.

In this example there are 4 drivers wish maps for 4 v/n ratios (vehicle to engine speed ratio). These act like gear ratios for all forward gears. The 5th map is probablly for All wheel drive vehicles and the 6th map is for reverse gear. A drivers wish map in text view looks like this;

The Y axis is engine speed (rpm) with a factor of 0.5 (all EDC17 seem to use a factor of 0.5 for rpm). The X axis is Accelerator pedal press ( 0 to 100%) with a factor of 0.012207 The Z axis (output) is Torque (Nm) with a factor of 0.1 To keep things simple I have set resolution to zero for all axes. (no decimal points).

Exhaust Gas recirculation (EGR) The area of the file with EGR maps usually looks like this;

You can see that Winols map search has found 5 possible EGR maps. They look the same as EGR maps in an EDC16 file. An EGR map in text view looks like this:

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Injection Quantity (mg/cycle) with a factor of 0.01 The Z axis (output) is Mass Air Flow as a percentage (0 to 100%) with a factor of 0.1 This is different to EDC16 files. In EDC16 files the EGR values for output are Mass Air Flow in mg/cycle so the numbers are usually in the range; zero to 1500 mg/stroke Air. Some EDC17 files use this EDC16 method. You need to look closely at the values to decide which system is used in the map.

Mass Air Flow EDC17 files include Mass Air Flow maps not found in EDC16 files. These maps may be used with the EGR maps or instead of the EGR maps. The Mass Air Flow maps look like this;

These maps are usually just before or just after any ‘typical looking’ EGR maps. A Mass Air Flow map in text view looks like this:

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Injection Quantity (mg/cycle) with a factor of 0.01 The Z axis (output) is Mass Air Flow (mg/cycle Air) with a factor of 0.1 In this example you can see that the minimum air flow is 250 mg/cyc Air and the maximum air flow is 1000 mg/cyc air. The output of the map is shoing the maximum amount of fresh air that is likely to be needed at a specific engine speed and Injection quantity. E.g. 12.0 mg/cyc fuel at 2000 rpm has a value of 500 mg/cyc air. 30.0 mg/cyc fuel at 2000 rpm has a value of 750 mg/cyc air. So for a higher Injection quantity more fresh air will be required. If we assume that the maximum mass air flow possible is 1000 mg/cy. Then; 55.0 mg/cyc fuel at 2000 rpm has a value of 1000 mg/cyc air. (the maximum). So at this point the EGR valve must be shut as the engine requires maximum (1000) fresh air. For 30.0 mg/cyc fuel at 2000 rpm with a value of 750 mg/cyc air the EGR could supply 250 mg/cyc exhaust gas (1000 – 750 = 250) and For 12.0 mg/cyc fuel at 2000 rpm with a value of 500 mg/cyc air the EGR could supply 500 mg/cyc exhaust gas (1000 – 500 = 500). If we assume a maximum of 1000 mg/cyc air, then 500mg/cyc air at 12.0 mg I.Q and 200 rpm is 50% Exhaust gas. So this point is equivalent to the 50% point on an EGR map that is percentage based.

Torque to Injection Quantity conversion The torque to IQ conversion maps in EDC17 are the same as in EDC16 E.g

Just like EDC16, there can be several maps. Often arranged in pairs like above. A Torque to IQ map in text view looks like this:

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Torque (Nm) with a factor of 0.1 The Z axis (output) is Injection Quantity (mg/cycle) with a factor of 0.01 * I have used as few decimal places as possible to keep view simple. Just like in EDC16. This map converts Torque (e.g from Drivers wish map) into an Injection Quantity. All EDC17 files are Torque based where as EDC16 files are either IQ based or Torque based.

Torque map The EDC17 torque map looks the same as an EDC16 torque map. E.g

In this case the torque map looks like FOUR little humps. A Torque map in text view looks like this;

The Y axis is Atmospheric Air pressure (hPa) with a factor of 0.1 The X axis is engine speed (rpm)with a factor of 0.5 The Z axis (output) is Torque (Nm) with a factor of 0.1 As the Y axis has four values we see 4 little humps in 2d view. If the Y axis has 3 air pressure values we see three little humps. The different air pressure values help the ECU consider Air pressure changes (mainly due to climbing mountains). Some files do not bother with this variation. They just have one little hump for a single atmospheric air pressure. It is up to the manufacturer to decide. Start of Injection (SOI) Most EDC17 files are for Common Rail Injection engines and the Start of Injection maps generally look like this;

Here you can see 5 maps, They are all very similar. Do not be fooled by the peak lines in the 3rd, 4th and 5th maps. These represent negative values.

In text view the Start of Injection map looks like this;

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Injection Quantity (mg/cyc) with a factor of 0.01 The Z axis (output) is Start of Injection Angle (crankshaft degrees) with a factor of 0.021973. * (edc16 files use a factor of 0.023437 for crankshaft angle) As usual I have kept the number of decimal places to a minimum. Be warned. Start of Injection maps are easy to find and to label as shown above BUT. It is very hard to work out what each map represents. Common rail injection systems use multiple injection events. e.g

This is a representation of possible injections. NOT a real example. In this example there are 5 injection events; Pilot Injection 1 Pilot Injection 2 Main Injection Post Injection 2 Post Injection 1

Post injection 1 is reserved for Catalyst regeneration. It occurs roughly 40 degrees after Top dead center (TDC) and so does not contribute to engine power. The other 4 injections provide the fuel for engine power. Like in EDC16 files, Most start of Injection maps are temperature dependent. This means that SOI usually has a temperature based selection map before the SOI maps start in the file. This map often selects 6 maps at six different temperatures. e.g -20.0 0

0.0 1

18.0 2

40.0 3

60.0 4

78.0 5

So a file can contain; 6 Pilot injection 1 maps 6 Pilot injection 2 maps (possible 6 pilot injection 3 maps) 6 Main injection maps Plus a varietyof post injection SOI maps. (These are not based on the above temperature selector) So do not be surprised to find 30 or more SOI maps. And you do not know which map is which. You may be able to work out which maps are Pi1, Pi2, Main etc by looking at the output values of SOI. BUT. Even if you can do this you have a further problem. In many files SOI maps are not arranged as Pi1, Pi2, Pi3, Main etc. Many files use SOI combination maps. E.g. Main injection without pilot Main Injection plus Pi1 Main Injection plus Pi2 Main Injection plus Pi1 & Pi2 Or any other combination that the manufacturer wants. Even with a DAMOS file as a help, it can be hard to work out which maps you are looking at.

SOI for PoI1. – a special case Post Injection 1 SOI maps look like this;

Here you can see four Post injection 1 maps. The high values being due to the fact that they will become negative values once a factor has been added along with a ‘sign’ e.g

For post injection SOI maps you must use the crankshaft angle factor of 0.021973 for the Z axis (output) and you must ‘tick’ the sign box. These maps are usually obvious because all the values are roughly - 40.00 degrees.

Injection Duration EDC17 file contain one or more Injection duration maps. Injection duration maps look like this;

If only one injection duration map is present it is used for all injections. Some files use a different injection duration map for each injection type. This file has only one map. Text view for ththis injection duration map looks like this;

The Y axis is injection Rail pressure (hPa))with a factor of 100 The X axis is Injection Quantity by Volume (mm3) with a factor of 0.01 The Z axis (output) is Injection duration (µs) with a factor of 0.4 As you can see, the general rule is that injecting more fuel takes more time so injection duration will get longer. Increased rail pressure with increased injection volume helps to reduce the increased injection duration. The injection duration map allows for increased rail pressure with increased injection volume.

Boost control – Boost actuator – N75 The Boost control in this example is for a VNT (variable nozzle Turbocharger) using a vane actuator or N75 valve and looks the same as in EDC16 files. Files often contain multiple versions of this map to allow different boost strategies. e.g.

In this picture you can see three boost control maps. This file actually has six boost control maps. In text view the boost control map looks like this;

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Injection Quantity (mg/cyc) with a factor of 0.01 The Z axis (output) is control value (percent) with a factor of 0.012207 On Startup of the engine the actuator output is 100% and the turbocharger vanes are closed to give maximum possible boost. As engine speed rises with increased injection quantity the cboost control

100% is steadily reduced which opens the turbocharger vanes to provide less boost. “wastegate” controlled system, the wastegate would be opening.

In a

The boost control map (N75) is for the ‘course’ control of boost. PID control loops are used for fine control to keep actual boost withing the requested boost range.

Boost map EDC17 Boost maps look the same as in EDC16. e.g

Here you can see four boost maps. (there are six in this file). In text view a boost map looks like this;

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Injection Quantity (mg/cyc) with a factor of 0.01 The Z axis (output) is Boost Air pressure value (hPa) with a factor of 1.0

As with EDC16 files, the map allows for boost to increase with engine speed and injection quantity up to a set point maximum. (2550 hPa in this case). In this way Boost maps are self limiting. A further limitation is available in most EDC17 files just like in EDC16 files. Boost limitation. To prevent the turbocharger ‘over speeding’ in thin air (less atmospheric air pressure) most EDC17 (just like EDC16) files include a turbo boost limitation map. Eg. This picture shows the file view and the text view of the boost limitation map.

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Atmospheric Air pressure (hPa) with a factor of 1.0 The Z axis (output) is Boost Air pressure value (hPa) with a factor of 1.0 At high atmospheric air pressure the maximum permissible boost is 2550 hPa and at lower atmospheric air pressure the maximum boost is limited. E.g Maximum boost for 3000 rpm at 600 hPa is 1950 hPa. This map is mostly important for vehicles operating in mountainous areas of the world where atmospheric air pressure drops as you drive at altitude. Rail pressure. EDC17 files include rail pressure maps similar to those in many EDC16 files. e.g

This image shows two rail pressure map types. The one on the left is is only relevant to the file designer as it relates to the mechanics of the system fitted to the vehicle. The map on the right shows the maximum permissible rail pressure available. All other rail pressure maps look similar to this one (but with lower values). NEVER try to exceed the values in this maximum map. Below view of four max Rail pressure maps used in this example file.

They look similar to the maximum rail pressure map. (but the pressure values are lower) In text view the maximum rail pressure map ( and other rail pressure maps) is like this;

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Injection Quantity (mg/cyc) with a factor of 0.01 The Z axis (output) is Rail pressure (hPa) with a factor of 100.0 In general more engine speed requires more injection quantity which requires increased rail pressure. The increased rail pressure helps to reduce injection duration. WARNING. Do not fiddle with common rail injection system mechanics with engine running. High pressure can cause serious injury or even death.

Smoke limitation EDC17 files, like EDC16 files use either Mass Air flow (MAF), Manifold Air pressure (MAP) or Lambda sensor values to limit Injection quantity and therefore avoid excessive engine smoke. In this example the smoke limitation map looks like this; There is only one smoke limitation map based on Manifold Air pressure (MAP).

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Manifold Air pressure (hPa) with a factor of 1.0 The Z axis is Injection Quantity (mg/cyc) with a factor of 0.01

As with EDC16, this map uses Manifold Air pressure as a guide to the amount of Oxygen available for fuel to burn without producing excessive smoke. Generally the Injection quantities in this map are held below those from the Torque limitation map. Starting Torque maps EDC17 Engine start maps look similar to those in EDC16. e.g

The map on the left is used for normal starting of the engine by the starter motor. The map on the right is an alternative map for when the starter motor is not available. In this case the maps look slightly different but the basic data is the same in both maps. The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is coolant temperature (°C) with a factor of 0.1 and offset -273.14The Z axis (output) is Injection Quantity (mg/cyc) with a factor of 0.01 The Z axis (output) is Torque (Nm) with a factor of 0.1

Swirl flaps. I am including a brief look at swirl flap maps as I get many requests relating to them. In this example file the swirl flap maps look like this;

The Y axis is engine speed (rpm)with a factor of 0.5 The X axis is Injection Quantity (mg/cyc) with a factor of 0.01 The Z axis (output) is control value (percent) with a factor of 0.012207 As with boost control the actuator value of 100% (95% in this example) means flaps fully open. In this example you can see that the flaps only close at low engine speeds and low Injection quantities. This file actually has 10 swirl flap related maps. Only three seem to be functional. The others are maximum/minimum values or corrections.