Diesel: DPF, AdBlue and glow plugs
Diesel will not start after running out of fuel: what to do
When a diesel runs out of fuel, air gets into the system, and after refueling it may not start until fuel reaches the high-pressure pump again. Many modern cars prime themselves if you switch the ignition on several times; others have a hand pump or need a shop.
Check without hurryDiesel: DPF, AdBlue and glow plugs
Reviewed by Daniel Morales, founder of Reprorace SL, on
Is it serious? Can I keep driving?
Usually not urgent, but do not ignore it. It is not dangerous, but do not keep cranking for long: you can drain the battery and strain the high-pressure pump running dry. If it will not start after following the owner's manual procedure, call for assistance.
A careful, general answer: only someone who inspects the car can say whether it is safe to drive. When in doubt, stop somewhere safe and call for assistance.
Most likely causes
- Air in the fuel system: the direct result of running out of diesel.
- Fuel filter: a filter with water or heavy dirt makes priming harder.
- In-tank low-pressure pump: if it does not push, the fuel does not arrive.
- Battery drained by the attempts: the engine cranks slowly and will not start.
Listed from more to less common in general; on your car they may be different. A fault-code reading and a check at the garage confirm which one it is.
To understand it better: Can I diagnose my car myself? What is live data and what is it for?
Car system: Fuel and air
What you can check yourself
Put in a decent amount of diesel, not just a little.
Switch the ignition on and off several times without cranking, waiting a few seconds: on many cars the tank pump primes the system.
If your car has a manual priming bulb, use it as the owner's manual explains.
Crank in short attempts with pauses so the starter and the battery can rest.
Safe checks only: with the engine off and cold whenever you look under the hood, without taking anything apart and without touching hot or moving parts.
Related fault codes
- P0087Fuel rail/system pressure: too low (bank 1)
- P0190Fuel rail pressure sensor (bank 1), circuit: malfunction
- P0627Fuel pump A, control circuit open
- P0230Fuel pump, primary circuit: malfunction
Generic codes that often come with this symptom. Seeing one does not confirm the cause: it is where the diagnosis starts.
How the ECO-LITE helps diagnose it
Plugged into the OBD socket, the ECO-LITE reads the fault codes of the control units that answer, with the freeze-frame data captured when the fault happened, and shows live data on your phone or computer. With your permission, your garage can see them remotely before you bring the car in.
What to look at here: fuel rail pressure while cranking, cranking speed and fuel pressure codes.
Frequently asked questions
Can running out of diesel damage the engine?
It can strain the high-pressure pump if you keep cranking it dry. The careful approach is to prime and crank with pauses.
Why will it not start when I have already refueled?
Because the fuel has to refill the lines and the filter all the way to the high-pressure pump.
Is it the same on a gas engine?
On a gas engine, refueling and switching the ignition on a few times is usually enough.
Keep reading
- Fuel and air: how it works and what fails
- Engine cranks but will not start: causes and what to do
- Car slow to start: causes and what to do
- Car stalls by itself: causes and what to do
- Car symptoms: what they mean and what to do
- Check engine light on: what to do
- How to read and clear your car's fault codes
- OBD fault codes: what each one means