P1240CriticalPowertrain

P1240 on 2009-2020 SEAT Ibiza (Reference, Style, FR, Xcellence) — Manufacturer-Specific Injector / Fuel System Circuit Fault

1 vehicles · 1 makes · $300-$1,800 repair

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How to diagnose and fix P1240: most-reported vehicles

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SEAT Ibiza · 2009–2020

The 1.6 TDI common-rail engine in Ibiza Mk4/5, Leon Mk2/3 (and across VW Group small diesels) suffers injector failure (Continental/Siemens VDO piezo injectors on the EA189 CAYB/CAYC) typically at 100,000-180,000 km. Symptoms: rough cold start, individual-cylinder misfire, sometimes back-leak overwhelming the rail pressure regulator. Injector copper washers often re-seal poorly after the first removal.

Common Symptoms

  • rough cold start
  • misfire
  • limp mode
  • fuel smell

How to Fix

Back-leak test (10 min) confirms diagnosis. Single injector replacement €300-€600 incl. coding. Full set (4) €1,000-€1,800. Use VW 507.00 spec oil and quality diesel from major-brand stations.

Typical repair cost:$300 - $1,800
Sources for this issue (1)

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Manually Verified
Medium ConfidenceUpdated Nov 7, 2026

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P1240 code reference

General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.

Frequently asked questions

What does P1240 mean?

P1240 stands for "Manufacturer-Specific Injector / Fuel System Circuit Fault." P1240 is a manufacturer-specific powertrain code, generally associated with a fuel injector or fuel-system circuit fault, though the exact assignment differs by manufacturer. On several platforms it indicates a problem in a specific cylinder's injector circuit (often referenced as cylinder 4) or a related fuel-control/power-supply issue. A fault here can disrupt precise fuel delivery and lead to rough idle, misfire, and reduced performance. Confirm the exact meaning with make-and-model service information.

What are the most common causes of P1240?

The most common causes of P1240 are: Faulty or open fuel injector (cylinder-specific), Wiring, connector, or harness fault in the injector circuit, Injector power-supply or ground problem, Corroded or loose electrical connections, Faulty injector driver in the PCM/ECM, Fuel-system pressure or delivery fault (some makes), Internal PCM/ECM fault. The specific cause varies by vehicle.

How much does it cost to fix P1240?

Repair costs for P1240 range from $300 to $1,800, depending on the vehicle and root cause.

Which vehicles are affected by P1240?

Au7o has documented P1240 across 1 vehicle models from 1 manufacturers: SEAT.

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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.