How to make a diagnosis of the injector

Many of the reasons for unsatisfactory performance motor with electronic fuel injection are associated with a loss of cylinder compression or a problem in the ignition system. If measurements of compression showed normal results, and the ignition is normal, then you can check is the fuel in the cylinders.

You will need

• - A set of keys;
• - screwdriver;
• digital multimeter;
• bulb light 12V with wires;
• - help partner.

Instruction

1. Remove all high voltage ignition cables from the electrodes of the spark plugs and remove one candle. This must be done to ensure that the engine wouldn't start. To disable low-voltage connector from the distributor is not necessary, as this may be the reason that the fuel pump will not turn on. Ask your partner to look at. does the fuel mixture from the spark plug hole. The team operate starter for 2-3 seconds. If the rotation of the engine cylinder crashes portions of the fuel mixture, so, in this cylinder the fuel is delivered. Check out all the other cylinders.
2. If there are obvious signs that the fuel is not fed into one of the cylinders, remove it from the spark plug. Remove the electrical connector from the injector and using a multimeter measure the resistance of the injector coil. It usually is in the range of 2-12 Ohms. If the device shows a short circuit, so in addition to replacing the injector will have to replace control unit injection.
3. In that case, if the device shows an open coil, it is advisable to ensure the serviceability of the output of the control unit. Measure the resistance of the serviceable injectorto know what is the current calculated output of the computer. It is necessary, in order to know how much wattage you can plug a light bulb into the socket of the injector.
4. Calculate the maximum current according to Ohm's law - current = voltage / resistance, assuming a voltage of 6 Volts. From this it follows that when the coil resistance is 12 Ohms, the current will be 0.5 a and the power lights no more than 6 Watts. Take the bulb from the dimensions on or off the backlight of the instrument panel, its power, usually 5 Watts, straighten it contacts, and insert the plug instead of the injector. Install back the removed high-voltage wire, connect a working injector, start the engine and look at the light bulb. At idle it will flicker. Add rpm, opening the throttle, the light bulb will burn smoothly and with increasing speed will increase the brightness. If this happens, it means that the engine control unit are OK, only need to replace the injector.