P0116 Weichai / Howo — water in fuel, causes and repair

Fault codes / P0116

SAE P0116 is coolant temp range. In the Weichai/Shacman ECU table in our database, P0116 is water in fuel (SPN 520264 FMI 11), next to P2269. Read the caption and SPN, not just the P-code.

Which trucks see it

WP10–WP13 on Howo, Shacman, Sitrak. After barrel fueling it pops often.

Symptoms

• MIL after fueling
• water-in-fuel lamp
• or odd coolant temp if it is the SAE path

Likely causes

• Real water in the separator.
• Stuck water sensor in the bowl.
• Open/short on that sensor.
• If the tool says coolant range — ECT sensor/thermostat. No OEM in the card.

What to check

1. Read SPN/text.
2. Drain the separator.
3. Clean the water sensor.
4. If coolant — live ECT from cold to hot.

Can you keep driving

After a drain you can usually drive. Lots of water — do not load, HP pump hates it.

Look up the code in the service

Other codes

• P0087 — low common-rail pressure
• P0193 — rail pressure sensor high signal
• P0299 — boost below target
• P0335 — crankshaft sensor no signal
• P0401 — EGR insufficient flow
• U0100 — lost communication with engine ECU
• P0562 — system voltage low
• P0201 — cylinder 1 injector circuit
• P2509 — intermittent ECM power (no OEM in DB)