P046C

EGR Sensor A Circuit Range/Performance

EGR / emissions Generic OBD-II Medium

What it means

P046C means the 'A' EGR feedback sensor is reporting a value that doesn't match what the ECM expects — the position or flow reading is out of range or doesn't track valve commands. It's an emissions-monitoring fault, commonly caused by carbon buildup on the valve or a drifting sensor, and rarely affects how the car drives.

Medium

Can I keep driving? Usually fine to keep driving short-term — an implausible EGR sensor reading is an emissions fault, not a no-start issue, but have it checked so EGR is controlled properly.

Real-world scan data

Seen in

733

scans in the past year

Found in

0.1%

of scans

0.2%

of scans that found faults

Appears alongside · share of P046C scans

P040Bin 65.8% of scans

P0401in 64.8% of scans

U029Din 64.5% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Often no noticeable driving symptoms
Possible pinging or rough running if EGR flow is misjudged
May fail an emissions/readiness test

Common causes

Most likely first

EGR position/feedback sensor 'A' reading out of expected rangeLikely
Carbon buildup preventing the valve from reaching commanded positionCommon
Wiring or connector fault skewing the sensor signalCommon
Sticking or slow EGR valveLess often
ECM/PCM fault (rare)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data and confirm the code with a scan tool.
Command the EGR valve open/closed and watch the sensor's reported position.
Inspect and clean the EGR valve, tube, and passages for carbon.
Check the sensor wiring and connector for damage or corrosion.
If the reading is still implausible with a clean valve, replace the sensor. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with P046C?+

Generally yes short-term — it's a sensor range/performance fault. Repair it so EGR is regulated correctly and to pass emissions.

Can I just clear P046C?+

It returns once the ECM sees the implausible reading again. The valve or sensor needs to be addressed.

Read & clear P046C yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX