Common rail injector diesel return check on Peugeot Partner 1.6 HDI

Test carried out on Bosch 1.6 HDI direct injection engine, test possible on different diesel engines with the CLAS kit adapters

Vehicle emits white smoke when starting, engine speed fluctuates slightly when cold (other possibilities...) then Carry out a diesel return test.

Before starting this tutorial, it is advisable to have at least new gaskets (green) for the diesel return rail fittings.

Remove the engine cover

Remove the clips from the diesel return fittings.

Disconnect the electrical connections from the injectors to facilitate disassembly of the return fittings/pipes.

disconnect the 4 diesel return connections from the injectors and plug them (here the white adapter plugs from the case were used, then place them on a cloth(s)) then reconnect the electrical connections for the rest of the test

Hang the tubes high up

Connect the pipes of the tubes to each injector and replace the clips (the return circuit is at low pressure but for the good holding of the pipes with the vibrations, it is advisable to replace the clips)

Start the engine, the test lasts between 2 and 3 minutes (do not fill the bottles to more than 8.5 on the scale to be able to recover the diesel present in the pipe)

Turn off the engine as soon as an injector reaches level 8.5, here the test shows that especially injectors no. 2 & 4 from the left send more diesel.

Injectors no. 2 and 4 must be cleaned before replacing them because their diesel returns are still drop by drop and the level difference with the other injectors remains correct.

Firstly, an injector cleaning with an additive product will be carried out as well as a new return test before undertaking a disassembly / cleaning of the injectors. (If the level difference is significant then proceed directly to the replacement of the leaking injector(s) concerned

Finally, place the bottles lower before disconnecting the test pipes from the injectors to recover the diesel in the bottles.

Proceed in reverse order to reconnect the diesel return pipes (replace the clips securely)