P0470 Code: Exhaust Pressure Sensor Malfunction
The P0470 code indicates an electrical fault in the exhaust pressure sensor circuit. The main effects are a loss of power and degraded turbo control. It is typical of turbo diesels, where the sensor tube clogs with soot very often.
- Severity
- Medium
- Can I keep driving?
- Yes, but with caution
- Estimated cost
- $50 to $400
- Difficulty
- Medium
- System
- Emissions Control
- Applies to
- All OBD2 vehicles
On this page
What the P0470 code means
The exhaust back pressure (EBP) sensor measures the back pressure in the exhaust manifold. It is typical of turbo diesels with a variable geometry turbo and an exhaust pressure valve, such as the Ford Power Stroke and International engines.
The sensor gets a 5 V reference and a ground from the computer and sends back a signal between roughly 0.5 and 4.5 V. A circuit fault, which is what the P0470 code reports, can come from the sensor, the wiring or the power supply.
The computer uses this pressure to control the turbo, the EGR and the exhaust pressure valve (which helps warm up the engine when cold). If the signal fails, the turbo and the EGR lose their reference and a loss of power usually follows. The tube that carries pressure to the sensor clogs with soot very often. Look up the sensor guide to see how it is tested.
Always start with the simplest things: fuse, relay and connector. Then check power, ground and signal with the part still connected (using back-probes), and finally the continuity of each wire to the computer. Only if all of that checks out should you replace the component.
P0470 code symptoms
- Check engine light on.
- Loss of power and degraded turbo control.
- Emissions monitor incomplete, so the vehicle cannot pass inspection.
- Loss of power or uneven running.
Likely causes of the P0470 code
- Damaged or corroded connector. The most frequent cause.
- Cut or shorted wiring between the component and the computer.
- Failed sensor, open or internally shorted.
- Missing power reference. Check whether other sensors are also failing.
- Computer. Uncommon.
How to diagnose the P0470 code step by step
- Read the sensor value on the scan tool and compare it with what you expect.
- Inspect the connector for corrosion, water or loose pins.
- Check the reference and ground with the key on (5 V, and less than 0.1 V of voltage drop on the ground).
- Measure the signal with the connector plugged in and see whether it changes with conditions.
- Do a wiggle test on the wiring.
- Check continuity to the computer.
- With the engine off, compare exhaust pressure and barometric pressure. They should match.
- Clean or replace the pressure tube from the manifold to the sensor, which often plugs with soot.
How to fix the P0470 code
- Repair the connector or the wiring.
- Replace the sensor if the tests confirm it is bad.
- Correct the real condition if there is one (a leak or a blockage).
- Clear the codes and complete a drive cycle so the monitor runs.
Technical reference data
- 5 V reference, ground and signal.
- Engine off: atmospheric pressure.
- Approximate values only: check the manufacturer data for your engine.
Brand-specific notes
The sensor tube is the first thing to check on diesels, because soot plugs it more often than the sensor fails.
P0470 on Ford
Very common on the Ford Power Stroke 6.0 and 7.3, where the sensor tube plugs with soot.
P0470 on International
Very common on International engines, where the sensor tube plugs with soot.
Questions about the P0470 code
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