Open Fuel Injectors, Checking

WARNING: This page is about a different car, the 2015 Audi Q7, 2014 Audi Q7, and 2013 Audi Q7. However, it is still accessible from the selected car via links, so may be relevant.

Open injector means: the nozzle needle does not close all of the way and fuel leaks into the cylinder.

Special tools and workshop equipment required

Hand Vacuum PumpVAS 6213
Vehicle Diagnostic Tester
Make an -adapter- out of a return line.

Procedure

-- Check the Diagnostic Trouble Code (DTC) memory and erase any faults. Use a Vehicle Diagnostic Tester.

-- Remove the engine cover. Refer to ENGINE COVER .

-- Clean all fuel rail connections with engine or brake cleaner and dry off.

NOTE:

Follow the rules of cleanliness. The fuel system must remain free of dirt.

Check one cylinder after another.

CAUTION:

Danger of malfunction caused by dirt.

Note, refer to FUEL SYSTEM SAFETY PRECAUTIONS

Begin with cylinder 1.

-- Push both tabs -1 and 2- downward and at the same time pull the center part upward -arrow- to unlock and remove the fuel return hoses from the fuel injectors.

Fig 1: Identifying Brackets

Courtesy of AUDI OF AMERICA, LLC

-- Connect the clean adapter that has been cleaned out using compressed air to the fuel return line connection on the injector that is being checked.

-- A vacuum pressure of -500 mbar (-7.25 psi) is applied using the Hand Vacuum PumpVAS 6213.

Fuel injectors are OK when the pressure remains constant for about 30 seconds.

Fuel injectors are defective when the pressure falls down to 0 bar within 2 to 3 seconds.

Repeat, if necessary, and pay special attention to the loss in pressure in the Hand Vacuum PumpVAS 6213.

-- Replace any defective fuel injectors. Refer to FUEL INJECTORS .