Ford · Ford 6.7 Powerstroke SCR SystemHigh

Ford 6.7 Powerstroke SCR Efficiency Codes

Guide P20EE (FMI N/A) — SCR efficiency and NOx sensor fault codes on Ford 6.7L Powerstroke diesel — P20EE, P2200, P2201, and DEF-related codes diagnosed with FORScan

4.8/5· 128 reviews

Quick Answer

6.7 Powerstroke P20EE means SCR efficiency below threshold. Use FORScan to read efficiency %, verify DEF at 32.5% urea, check NOx sensor voltage 0.5–4.5 V, and smoke-test exhaust leaks before SCR catalyst replacement.

Overview: Ford Guide P20EE

Ford 6.7L Powerstroke SCR efficiency codes like P20EE are common on 2011–2022 trucks — but catalyst replacement is rarely the first fix. Bad DEF, failed DEF pump, exhaust leaks, and NOx sensor circuit faults cause the same P20EE before the SCR brick actually fails.

Repair Snapshot

Time

2 - 5 Hours

Difficulty

Advanced

Parts Cost

$200 - $5,000

Dealer Labor

$500+

Tools Required

  • FORScan
  • Noregon JPRO
  • DEF Refractometer
  • Multimeter

What Guide P20EE Means

Ford 6.7 Powerstroke SCR efficiency codes include P20EE (SCR NOx catalyst efficiency below threshold), P2200/P2201 (NOx sensor circuit), and P2080/P2084 (exhaust temp sensor). FORScan reads live SCR efficiency %, DEF level, and NOx sensor values. Verify DEF at 32.5% urea, DEF pump pressure, and exhaust leaks before SCR catalyst replacement on 6.7 Powerstroke.

Symptoms Drivers Notice

  • P20EE SCR NOx catalyst efficiency below threshold on 6.7 Powerstroke
  • P2200 or P2201 NOx sensor circuit faults
  • Reduced power with check engine light on 6.7 Powerstroke
  • DEF consumption drop in FORScan live data
  • P2080 exhaust gas temperature sensor fault paired with SCR codes

Most Likely Root Causes

Off-spec DEF below 30% urea

Common

P20B9 DEF quality sets first, then P20EE SCR efficiency follows within drive cycles.

DEF pump or doser failure

Common

Zero DEF consumption with active SCR demand — dosing failure drops efficiency below threshold.

Exhaust leak upstream of SCR

Occasional

Flex pipe crack dilutes NOx readings — false P20EE and P2200 codes.

Common Misdiagnoses (Don't Waste Parts)

SCR catalyst replacement on first P20EE

Why it happens: Code description names SCR catalyst efficiency.

Do this instead: Parts-cannon trap — confirm 32.5% DEF, DEF consumption, and NOx sensor voltage before catalyst quote.

Replacing NOx sensor without circuit test on P2200

Why it happens: Code names NOx sensor circuit.

Do this instead: Measure sensor signal 0.5–4.5 V at connector — FMI 5 open circuit vs FMI 3 shorted high need different fixes.

Master Tech Commentary

Mechanic's Notes

6.7 Powerstroke trap: cracked exhaust flex before SCR reads as P20EE — smoke test at 15 PSI before $3,000 catalyst. DEF heater failure in winter stacks P20B9 then P20EE within one cold night.

Step-by-Step Diagnostic Procedure

  1. Step 1: Connect FORScan to 6.7 Powerstroke OBD port, read active codes — note P20EE, P2200, P2201, and companion DEF codes P20B9 or P20E8.
  2. Step 2: Monitor SCR catalyst efficiency % in FORScan — must exceed 70% at steady cruise; below 50% with good DEF points to dosing or catalyst fault.
  3. Step 3: Refractometer test DEF tank — 6.7 Powerstroke expects 32.5% urea at 68°F; below 30% sets P20B9 DEF quality codes that stack with P20EE.
  4. Step 4: Check DEF pump operation in FORScan — commanded vs actual DEF level change during drive cycle; no consumption with active SCR demand means pump or doser fault.
  5. Step 5: Measure upstream NOx sensor signal voltage at connector — should fluctuate 0.5–4.5 V during engine run; stuck at 0 V or 5 V confirms P2200/P2201 wiring or sensor fault before catalyst order.

Professional service / OEM-level scan tools are recommended before clearing this fault for good.

Live Data & Freeze-Frame Tips

FORScan 6.7 Powerstroke: SCR efficiency %, DEF level %, DEF tank temp, upstream NOx mg/mol, downstream NOx mg/mol, and exhaust temp at SCR inlet — log during 10-minute steady cruise.

Safety Warnings

  • 6.7 Powerstroke SCR exhaust exceeds 1,000°F during regen — clear area.
  • DEF corrosive — gloves when handling pump or doser service.

When to Limp In vs Tow

Tow 6.7 Powerstroke with P20EE plus severe power reduction and DEF system confirmed inoperative.

Prevention Tips for Fleets & Owner-Operators

  • Use API-certified 32.5% DEF from sealed containers.
  • Refractometer test DEF at oil change interval on 6.7 Powerstroke.
  • Inspect exhaust flex pipe at every service — crack causes repeat P20EE.

Related Fault Codes

P20B9

DEF quality out of spec — common root before P20EE on 6.7.

P2200

NOx sensor circuit — check 0.5–4.5 V before SCR catalyst on P20EE.

Frequently Asked Questions

What does P20EE mean on 6.7 Powerstroke?

SCR NOx catalyst efficiency below threshold — verify DEF and dosing before catalyst replacement.

What SCR efficiency should 6.7 Powerstroke show?

Above 70% at steady cruise in FORScan with good DEF and normal dosing.

Can bad DEF cause P20EE?

Yes — P20B9 DEF quality often sets first, then P20EE follows within one or two drive cycles.

Which scan tool reads 6.7 Powerstroke SCR data?

FORScan with extended license, Ford IDS, and Noregon JPRO on OBD-equipped 6.7 trucks.

How do I test 6.7 Powerstroke NOx sensor?

Measure signal voltage at connector during engine run — expect 0.5–4.5 V fluctuation, not stuck at 0 or 5 V.

Guides that go deeper