LED for simulating injection pulse

one of the aggreed outcomes of this project is that we should include the fuel system. however when the atomized fuel meet with sparks from the spark plugs, dangerous can happen. under safety concideration, our superviser have agreed to cancle out the application of fuel pump. without the fuel pump runs fuel into the injectors, we have to use LED to simulate injection pulses.

If an LED were connected directly across a 12 volt battery, it would light brightly, but only for a few seconds. Excessive current can destroy the P-N junction. The average LED requires only about 20-30 mA. So a resistor must be connected in series with every LED to control current flow. The method we have used to protect the LED is to connect a 470 ohm resistor in series with each LED. The resistor can be connected to either the anode or the cathode end.

project frame

now it comes to a new process. since we have tested all the components which are working correctly. the next task is to make a board to make it look nice and easily move around. again, if you have special skills, you will find out you can rely on them at any time and anywhere. Tony has the whole set of tools to make wooden projects. we calculated all the woods we are gonna need to make the demen

before comes to this point, Tony actually has spent a lot time to make all the mounts for the components. he is not only a good lecturer also a good carpenter. it takes so much time and patience. but he has been quite enjoying it. and all i can do is to hand over the tools he needs. there is nothing more i can do so far.

emergency protection

Fuses are used in circuits to protect the wiring from overheating and damage caused by excessive current flow as a result of a short circuit or other malfunction. Since this project is about to build an EFI system, so only limited fuses which are needed to protect the circuits. During the testing of the project we burned a few fuses. It is so wise we have built the fuse panel into the system.

and also all the wiring connection we used heat shrink tube to prevent moisture

nightmare: nothing happens

when we assembled  the system to test if all the components were working correctly, there was no fuel and no spark. As we know most electronic fuel-injection computer systems use the pick-up coil or crank sensor pulse as the trigger for when to inject fuel from the injectors. If this signal were not present, no fuel would be injected. Because this pulse is also necessary to trigger the module to create a spark from the coil, it can be said ‘no fuel, no spark’ situation. So we spent hours on testing the distributor and wiring to find the problem. Fortunately, we found out that the distributor was not earthed. When a distributor in a vehicle, it is earthed to the engine body through the metal mounts. Since now it is mounted onto a wooden board, the distributor must be earthed to the battery negative.