The electronic module converts the low voltage into the high voltage required for the ignition system to operate. The function of the components mentioned is described below, which is also relevant for the 4-cylinder engine with fuel injection.
There is a plate on the side of the module when the carburetor is installed (see illustration 1.1), which shows the ignition timing curve. The numbers behind the "RE" mark are very important, as they also determine the ignition timing.
1.1 Location of the nameplate with installation data on the control unit
(The text is available on this website: renaultbook.ru)
Illustration 1.2 shows the components of an electronic ignition system, together with the connections on a carburettor engine. Illustration 1.3 shows the components of the system on a fuel-injected engine. The difference is mainly in the connection method.
1.2 Components of the electronic ignition system in a carburetor engine 1. To the positive terminal; 2. To the mass; 3. To the tachometer; 4. Ignition timing sensor; 5. Ignition timing sensor; 6. Screen; 7. Positive terminal of ignition coil; 8. Negative terminal of ignition coil; 9. Positive ignition coil cable; 10. Negative ignition coil cable; 11. Positive input of the electronic module; 12. Secondary connection; 13. Mass of the electronic module; 14. Tachometer output; 15. Ignition timing sensor pulse; 16. Ignition timing sensor pulse; 17. Screen; 18. Cover separating the breaker from the ignition distributor; 19. Ignition coil; 20. Vacuum ignition advance regulator; 21. Electronic module; 22. Ignition timing sensor; 23. Flywheel
1.3 Components of the electronic ignition system 1. To the positive terminal; 2. To the mass; 3. To the tachometer; 4. Ignition timing sensor; 5. Ignition timing sensor; 6. Positive terminal of ignition coil; 7. Negative terminal of ignition coil; 8. Positive terminal of ignition coil; 9. Negative terminal of ignition coil; 10. Connecting wire; 11. Positive input of the electronic module; 12. High voltage output of the secondary winding; 13. Module mass; 14. Tachometer output; 15. Ignition timing sensor pulse to; 16. Ignition timing sensor pulse; 17. Cover separating the breaker from the ignition distributor; 18. High voltage ignition coil; 19. Vacuum ignition advance regulator; 20. Electronic module; 21. Ignition timing sensor; 22. Flywheel
The flywheel ring gear has 44 teeth that are evenly distributed around the perimeter, but at 180° intervals, two teeth are missing, so the TDC sensor can accurately indicate the 90° BTDC and BSDC marks.
The TDC sensor detects both the dead center position and the engine speed and sets the ignition timing that best matches the engine speed. Figure 1.4 shows the parts described.
1.4 Ignition timing sensor in the flywheel housing in the upper figure, and the location of the flywheel teeth in the lower figure
The vacuum advance regulator acts like a normal regulator in a conventional ignition system and adjusts the ignition timing according to the engine load (for carburetor engine only).
On vehicles with fuel injection, there is a manifold absolute pressure sensor that sends an electrical pulse to the electronic module to set the injection timing.
The ignition coil operates separately from the module and can also be replaced separately. On a carburetor engine, the ignition coil is installed in the ignition control unit, and on a fuel-injected engine, it is installed separately.
The computer controlling the ignition system of the fuel-injected engine determines the ignition advance in accordance with the engine speed and the reduced pressure in the engine. Setting the ignition timing is only possible on carburetor engines.
If any of the electrical connections need to be disconnected, refer to illustrations 1.2 and 1.3 for subsequent connections. Remember that a short circuit can damage the electronic components of the system.
Ignition system - V6 engine
The ignition system of the V6 engine is based on the ignition system of the 4-cylinder engine. The following is a brief description:
- A full stroke of a four-stroke engine is achieved in two crankshaft revolutions (720°), i.e. in a six-cylinder engine an ideal ignition pattern is achieved when the combustible mixture is ignited every 120° of the crankshaft revolution. The crankpins of the Espacc engine move by 30°, i.e. TDC is set every 90°. One of the cylinders of each row is always at TDC.
- How to find the first cylinder? As you can see in Illustration 1.5, the left row contains cylinders #1, 2 and 3 (cylinder bank A), and in the right row - cylinders No.4, 5 and 6 (cylinder bank B).
1.5 Arrangement of cylinders in rows (A) and (B) on a V6 engine. The engine is turned with the (C) side. Cylinder #1 is on the flywheel side
These directions are defined, provided that you look at the engine from the "C" side. As you can see in the figure, cylinders No.1 and No.4 are on the flywheel side. If you turn the crankshaft so that the piston of the first cylinder is set to TDC (both valves of this cylinder are closed) and from this position turn the crankshaft further, the remaining pistons will be set to TDC in the specified sequence: 6-3-5-2-4, i.e. the firing order: 1-6-3-5-2-4.
The contacts in the ignition distributor are spaced at 60° intervals (360° in total), so that the next cylinder is reached with each crankshaft revolution.
To check if the correct piston is at TDC, look through the hole in the flywheel housing and remove the cylinder head covers 4, 5 and 6. The mark on the flywheel should be aligned with the "0" mark on the clutch housing, as shown in Illustration 1.6. The valves of the fifth cylinder should switch, i.e. one valve closes and the other opens. Cylinders working in "pairs": 1 and 5, 2 and 6, 3 and 4. The remaining cylinders can be set to TDC in the same way.
1.6 This is how the mark on the flywheel should be positioned in relation to the "O" mark on the clutch housing. On top for models with a manual transmission, on the bottom - with an automatic transmission