pravus

Hi,

I've just had my B8 RS5 carbon cleaned by walnut blasting. Garage confirmed it was all good but the day before I was going to collect it they said an engine light had come on.

I couldn't pull all the codes but could see misfiring across several cylinders and knocking.

They are now suggesting they it's nothing that they have done and they becuase the engine is now "so efficient" it has caused the injectors to fail.

Plausible or am I being taken for a ride?

hahnmgh63

Taken for a ride. Possibly they didn't install the injectors correctly or replace the Teflon seal. Some have just done the O-rings and not the Teflon seals and they need to be replaced too. Hopefully they didnt' get any Walnut media into the cylinders.

pravus

The garage has now tested the injectors and all 8 failed....

They are still suggesting it's somehow not their fault but I've no idea how I go about proving otherwise other than taking them to small claims court.

kelisko

Tell them the technician who did the cleaning very likely did not cover the top of the injectors when performing the walnut blasting procedure of the intake ports and valves. Falling walnut shell grains likely entered the injectors and clogged them. My video below will give you an idea of what may have happened. You can see the 6 injectors covered in the middle of the engine (4 green covers, 1 yellow, 1 white). See how easy the flying walnut shell grains could land into the injectors if they are not covered? They are all over the pace and even in my hair. You can see me vacuuming them around all the time.

hahnmgh63

What Kelisko said, an incompetent Tech for sure. Especially if there are multiple injectors failed. Should have pulled them all to install new seals anyways and probably depending on the mileage should have sent them out for cleaning.