All codes › P0402
P0402: Exhaust Gas Recirculation "A" Flow Excessive Detected
What it means
Too much exhaust gas is flowing through the EGR system, often causing rough idle.
Severity: Medium Excess EGR causes rough idle or stalling.
Common causes
- EGR valve stuck open
- Faulty EGR solenoid
- Faulty DPFE sensor
- Vacuum line misrouted
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Sometimes DIY. A stuck-open valve can be checked by tapping or vacuum test.
Repair cost
SEEDED ESTIMATE Roughly $260–$480
Most likely repair: egr valve. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| EGR valve | $164 | $164 | Typical listed retail range, source (single example listing ($163.99)) |
| Labor 1–2 hr | $100 | $320 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0402 are verified.
Verified reader invoices for P0402: 0. Share your repair bill to help build real costs.
Tools that can read P0402
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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