From years of wrenching on all sorts of rigs-diesels, gas, you name it-I can tell you that P0473 is the code your car throws when it’s got a problem with the electrical side of the exhaust gas pressure sensor circuit. You’ll spot this sensor on plenty of late-model engines, especially diesels with turbos and DPFs-think Ford’s 6.0L Power Stroke, EcoBoosts, Cummins 6.7L or 3.0L, even some Mercedes and Nissan trucks. The sensor’s job is to keep tabs on exhaust gas pressure, which lets the computer juggle emissions and turbo boost just right. Now, if that sensor’s output doesn’t line up with what the ECM expects-maybe it’s way off compared to intake or ambient readings-the computer throws P0473. Here’s the key: this isn’t about clogged pipes or stuck valves. It’s all about the wiring, connectors, or the guts of the sensor itself.
DTC P0473
6447
5 minutes of readingCauses of P0473 engine code
From experience, the most common reasons for p0473 are electrical in nature. Here’s what I usually find when I’m diagnosing this code:
- A break in the ground wire for the exhaust gas pressure sensor
- A break in the signal wire between the sensor and the engine computer (PCM)
- A short to voltage in the sensor’s signal circuit-sometimes the wire rubs through and touches a power source
- A failed exhaust gas pressure sensor itself, often due to an internal short
- Rarely, a faulty PCM (engine computer), but that’s the last thing I suspect after all other checks
Symptoms of obd code P0473
When p0473 is active, you’ll probably notice a few things. The check engine light will come on, and you might feel a loss of power, especially if your vehicle has a turbo. In some cases, you won’t be able to do a manual regeneration to burn off soot in the diesel particulate filter, which can eventually lead to a no-start condition if ignored. Basically, the engine may feel sluggish, and you could get stuck with a clogged filter if this isn’t addressed.
Diagnosis steps for P0473 code
Here’s how I tackle p0473 step by step, and you can do some of these checks yourself if you’re comfortable. First, I always check for any technical service bulletins (TSBs) for your specific vehicle-sometimes the fix is as simple as a software update. Next, I locate the exhaust gas pressure sensor and inspect the wiring and connectors. I look for chafed wires, melted insulation, or corrosion on the terminals. It’s best to have someone help you wiggle the harness while you watch for changes. If I see green corrosion or burnt pins, I clean them with electrical contact cleaner or rubbing alcohol and a soft brush, then let them dry and apply dielectric grease. After that, I clear the code and see if it comes back. If it does, I break out the multimeter. I check for proper 5V power supply to the sensor, make sure the ground is solid, and verify the signal wire isn’t shorted to voltage. If I find 12V where there should be 5V, that’s a big red flag for a wiring short. If all the wiring checks out, but the code keeps returning, I swap out the sensor. Only if the problem still isn’t fixed do I start suspecting the PCM, but honestly, that’s pretty rare.
Common Mistakes with dtc P0473
I’ve seen folks jump straight to replacing the sensor without checking the wiring first, and that’s a surefire way to waste money. Another common mistake is overlooking corrosion or loose pins in the connectors-those little details can cause big headaches. Skipping the TSB check is another one; sometimes there’s a known fix that gets missed. Always start with the simple stuff before replacing parts.
Seriousness of P0473
This isn’t something you want to ignore. If you let p0473 go, you risk clogging your diesel particulate filter, which can lead to expensive repairs or even a no-start situation. The engine can lose power at the worst possible time, and you might find yourself stranded. Plus, running with a faulty sensor can cause the engine to run less efficiently and pollute more. It’s not just about performance-it’s a real safety and reliability concern. Parts that can be damaged if this is ignored include the DPF (diesel particulate filter), turbocharger, and even the engine itself if things get bad enough.
Repair steps for obd2 code P0473
Most often, the fix is repairing or replacing damaged wiring or connectors at the exhaust gas pressure sensor. Cleaning up corrosion and making sure all connections are tight goes a long way. If the wiring is good, replacing the sensor itself is the next step. In rare cases, a PCM reflash or replacement may be needed, but that’s not common. Always clear the code and test drive to make sure the problem is gone before calling it fixed.
Conclusion
If you ask me, P0473 is one of those codes that’s easy to overlook but can cost you big if you let it slide. It’s pointing right at an electrical issue in the exhaust gas pressure sensor circuit, and that’s crucial for keeping your engine running clean and strong. Don’t drag your feet on this-take a close look at the wiring and connectors, check for any TSBs, and only swap the sensor if the wiring checks out okay. That’s how you keep your ride reliable and avoid those wallet-busting repairs down the line.
