Genuine Audi 90 Fuel Injector

Audi 90 Fuel Injector Parts and Q&A

• Injector
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  Q: What features do the fuel injector, idle control valve, and throttle position sensor include for fault diagnosis and engine testing on Audi 90?

  A:

  Mono-Jetronic system has the fault memory of the system, which may be accessed with a coded read-out and a warning lamp on the instrument panel lights up in case of fault, which are also utilized to recall fault memory code. In case the engine does not start, the amount of time to run the starter is approximately six seconds with the ignition on; in case the engine starts it should be left to idle. The known good fuse must be crossed over the relay test contacts of the fuel pump test contacts and at least five seconds should be allowed to pass after which the fuse should be disconnected and the number of flashing impulses of the warning lamp is recorded. A code 4444 means that there are no faults and the test is to be repeated till a code 0000 is obtained which means that the test is over. The flashing codes are also associated with different parts, including throttle valve positioner and the control unit. In order to cancel individual codes, the ignition off disconnection of the control unit wiring at least thirty seconds is required to clear the fault memory and five seconds ignition on followed by removal of the fuse to clear the fault memory. In the case of idling switch/control valve, the ignition is switched on and throttle valve is opened and closed to confirm the presence of clicks by the control valve, and in case of no clicking, a diode test lamp is applied to confirm the wiring. Engine is supposed to be run at idle speed and wiring plug is supposed to be removed and reconnected to note the difference in the engine speed. The throttle valve positioner needs battery power to be connected to the throttle valve positioner terminals to verify the movement of the plunger and the clearance may need adjustment. The working of the switch is tested by means of an ohmmeter. Resistances of throttle positioner and potentiometer are also observed and distinct behaviors recorded at throttle opening. Injector is sprayed pattern and leak checked and the resistance measured to a given level. Lastly, in the case of manual gearbox models, the throttle damper is set so that the throttle functions correctly when closed by plunging the throttle body.