Injectors leak off

[Dm85]

Hi all,

Been trying to track down more underlying engine vibrations at idle. Changed engine mounts, had a new flywheel recently. no fault codes. Took off auxiliary belt and ran the engine to eliminate the associated parts.

So thought I’d do a primitive leak off test on the injectors main return line. In one minute I had roughly 40mm of diesel fuel gather in the container. This could be from one or all injectors. I will do a more precise test of each injector soon.

Is that a normal amount of fuel to see gather in 1 minute at idle?

Any advice appreciated.

 

[Dellmassive]

Umm.........

 

[DXX]

Hi all,

Been trying to track down more underlying engine vibrations at idle. Changed engine mounts, had a new flywheel recently. no fault codes. Took off auxiliary belt and ran the engine to eliminate the associated parts.

So thought I’d do a primitive leak off test on the injectors main return line. In one minute I had roughly 40mm of diesel fuel gather in the container. This could be from one or all injectors. I will do a more precise test of each injector soon.

Is that a normal amount of fuel to see gather in 1 minute at idle?

Any advice appreciated.

View attachment 240168

Pretty sure the spec’ is on the Forum somewhere. It maybe specific to the engine code (type).

 

[Dm85]

Pretty sure the spec’ is on the Forum somewhere. It maybe specific to the engine code (type).

Thanks mate, to be fair that wasn’t testing each individual injector as it was the combined return hose. But I am going to push the boundaries and get a leak off kit. Sick of mechanics misdiagnosing and charging a fortune…..only thing Is the charge cooler is on top of and obviously need to either remove the whole assembly or thinking releasing the bolts in the bracket will give enough access to the injectors underneath….. if not is it ok to start the engine with it removed? Linking the coolant lines? Hard to link the air flow pipes!

 

[Dm85]

Umm.........

I guess I need to check each actual injector leaking now. That could be from all or one

 

[Dm85]

He explains the leak off test here but not specific to the T6 around 12 mins in

 

[n10n]

 

[DXX]

Thanks mate, to be fair that wasn’t testing each individual injector as it was the combined return hose. But I am going to push the boundaries and get a leak off kit. Sick of mechanics misdiagnosing and charging a fortune…..only thing Is the charge cooler is on top of and obviously need to either remove the whole assembly or thinking releasing the bolts in the bracket will give enough access to the injectors underneath….. if not is it ok to start the engine with it removed? Linking the coolant lines? Hard to link the air flow pipes!

As @n10n said above. Without the induction system installed the MAF would not be registered correctly.

 

[Dm85]

Logged the fuel rail pressure at idle and I’ve noticed the revs drop and the engine stutters slightly for a few seconds intermittently at idle, and managed to capture that in the fuel rail log. You can see the rail pressure spikes whilst I feel the engine hiccup.

Injector possible?






Seem