Strange noises in the night

Several times now in the past month I've walked past our parked Goliath out to the barn or somewhere and have done a done a double-take upon hearing the Sprinter singing to itself. The sound is similar to the 90-second EGR cleaning cycle but comes from the other side of the engine and was happening at least 30 minutes after the van had been parked.

Anyone noticed anything similar? The Rest heater was NOT turned on (I checked). What would the ECU be thinking about with the key off so long after being driven?

We also have rough idle right after starting the engine. What can cause rough idle in a diesel, given that they don't have a carburetor? This has persisted through several tanks of fuel.

My girlfriend noticed odd sounds coming from my Sprinter after it had been parked for a while. She described- similarly to what you're saying - higher-pitched sounds coming from the front of the van, but I haven't witnessed it myself. I don't think the phenomenon is documented.

As for rough idle, the Engine Control Module (ECM) is responsible for reading many sensors and doing many things based on those readings, to keep the engine running like it should under most conditions.....


These ECM contributions include

- adjusting fuel injection timing
- adjusting the amount of exhaust gas that gets dumped back into the intake system
- energizing glow plugs just after start up (yes, just because the glow plug light isn't lit on your dashboard, doesn't mean the ECM isn't using glow plugs to help the combustion process when your engine's cold)
... and the list probably goes on...

I think you'll have to have it diagnosed in person to determine root cause and have it remediated. It might be simple like an almost clogged filter, or fuel on the verge of gelling, but it also might be "involved," as in looking for an electrical problem giving bogus info to your ECM....

-Jon

Here is a wild ass idea. Could it be a bleeding of compressed gas within the A/C system? My home refrigerator sometimes makes a hissing sound sometime after it shuts off.

Taking it to the dealer today for the rough idle and to make sure they did everything for the 30k service, since they forgot to reset the warning. We are heading from MI to TX for my little sister's wedding over New Years and don't want a repeat of our AZ trip when the EGR failed in the middle of nowhere after our local dealer said everything was fine.

Nathan

Diamondsea said:

Here is a wild ass idea. Could it be a bleeding of compressed gas within the A/C system? My home refrigerator sometimes makes a hissing sound sometime after it shuts off.

Click to expand...

Don't know about the NCV3, but my T1N '02 makes noise after shutdown which is due to air bleeding into the vacuum system.