Refill AdBlue and Check the Level

The W907 Sprinter’s diesel exhaust system uses AdBlue, a urea solution (ISO 22241) that lets the after-treatment meet EURO 6. When the on-board computer warns the level is low you need to top it up before the van limits its speed and eventually refuses to start.

To check the level, open the on-board computer’s Service menu and select AdBlue. The display shows how much is left in the 22-litre tank. The cluster escalates its warnings as the reserve runs down: first “Refill AdBlue / see manual”, then “Refill AdBlue, limp mode XXX km”, then the speed is capped at 20 km/h with a “no start after XXX km” message, and finally the engine will not start at all. Refill before the first warning where you can.

1. Open the bonnet to reach the AdBlue filler (it is in the engine bay, not by the fuel filler).
2. Remove the cap: a plain cap twists off anticlockwise; a lockable cap needs the release tool from the on-board toolkit — lift the cap’s cover, insert the tool into the holes and turn anticlockwise.
3. Refill using one of these methods. Canister with a one-way hose: screw the hose onto the canister, screw or insert it into the van’s filler, then raise and tilt the canister — it stops when the tank is full. Screw-on bottle: screw the bottle onto the filler opening hand-tight and press down; the tank fills over up to about a minute and stops when you stop pressing. Filling-station pump: use the AdBlue car or truck nozzle and take care not to overfill.
4. Add enough to clear the warning: at least 8 litres when the cluster has prompted you, or at least 2 litres for a routine top-up.
5. Refit and tighten the cap (use the tool again for a lockable cap) and close the bonnet.
6. Switch the van on for at least 60 seconds, then start the engine so the system re-reads the level.

Good to know

Never add anything else to AdBlue — no additives and no dilution — and never put AdBlue in the fuel tank or fuel in the AdBlue tank. Wipe any spill with water straight away, as AdBlue crystallises as it dries.

AdBlue freezes at about -11 °C. The van has a tank heater so winter running is fine, but after a cold refill the cluster level can read incorrectly until you have driven for around 20 minutes. If a warning stays on after refilling, the SCR system may have logged a diagnostic trouble code that needs reading. Running without AdBlue is an emissions and type-approval offence in many countries.

FAQ

How much AdBlue does the Sprinter hold?

The W907 Sprinter’s AdBlue tank holds 22 litres.

Where is the AdBlue filler on a Sprinter?

Under the bonnet, in the engine bay — not next to the diesel filler. The cap is either a plain twist-off or a lockable type that needs the release tool from the on-board toolkit.

How much AdBlue should I add?

Add at least 8 litres once the cluster has prompted you, or at least 2 litres for a routine top-up. Do not overfill.

Why won’t my Sprinter start?

If AdBlue runs out completely the system enforces a no-start: the van is first limited to 20 km/h, then will not start until you refill. Add at least 8 litres and re-read the level.

What do I do after refilling?

Switch the van on for at least 60 seconds, then start the engine so the on-board computer re-reads the AdBlue level.