Powertrain, generic (extended)

P240F EGR Slow Response

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P240F means the EGR system takes too long to follow a changed flow target. CARB has required diesel OBD to catch such slow response since model year 2010. VW's 2014 data call it EGR System Dynamic Check on the 2.0 TDI (CJAA) and rate rising and falling target air mass against a characteristic above 20; the Touareg 3.0 V6 TDI (CNRB) uses 35 for falling and 30 for rising demand. Volvo and Mack 2018–19 trucks may log P240F-00 with P0069, P0191 and P10EC; if two or more appear, solution K33593604 calls for a new engine harness. Hyundai traced it on 2024 Tucson and Sonata 2.5 GDI to an EGR valve sensor fouled by solder flux (24-01-080H). Too little or too much flow: P0401/P0402.

Likely causes

Carbon-coated EGR valve moving sluggishly
Faulty position sensor in the EGR valve (e.g. Hyundai solder-flux contamination)
Intermittent fault in the engine harness (Volvo/Mack D11/D13)
Engine software requiring an update

Symptoms

  • Check engine light
  • Hesitation or smoke during load changes
  • Engine power derate on heavy trucks

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€100–1,500
Time0.5–5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

egr valve aegr cooler a

Related codes

P0401P0402P0404P049DP0405P2413

References: law.cornell.edu, static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.