P2291Injector Control Pressure Too Low - Engine Cranking
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2291 judges pressure build-up while the starter is turning. On HEUI diesels the injectors only fire once injector control pressure has reached a minimum, so any leak in the pressurised oil circuit shows up as a long crank or a no-start; Wikipedia's Power Stroke article names a contaminated injection pressure regulator and failed high-pressure oil seals as typical no-start causes on the 6.0 L. Ford also reuses the code on its current common-rail diesels: the 2023 summary for the 3.0 L and 6.7 L sets P2291 when rail pressure stays under 14,000 kPa for 20 s of cranking. Ford's 2014 PCM code table lists the code as well. Unlike P2290, which watches the running engine, P2291 covers only the start phase.
- What you may notice
- Engine cranks long or does not start
- Starts only after repeated attempts
- Check engine light after the start attempt
- Likely causes
- LikelyLeak in the high-pressure oil (HEUI) or fuel (common rail) circuit
- PossibleInjection pressure regulator or rail pressure valve not sealing
- PossibleHigh-pressure pump delivering too little at cranking speed
- RareLow cranking speed from a weak battery or starter
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €150 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.