P21D5Cylinder 7 Injector B Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P21D5 belongs to V8 engines with a second injector per cylinder. Two are documented: Ford's 5.0 V8, which gained direct injection alongside its port injectors in 2018, and GM's 2019 LT5, the supercharged Corvette ZR1 engine with primary direct and supplemental port injection. Ford's summary lists P21CF to P21D6 as port injector circuits, continuous above 11 V, 5 s. On the LT5 the B injectors hang on a separate injection module whose low-side driver flags an open at 200 kOhm or more with the output off, in 20 of 25 samples at 100 ms, Type A with MIL in one trip. Ford counts its V8 one bank after the other, so cylinder 7 lies on the second bank; GM alternates banks, making 7 the last cylinder on the left. The A-side code for cylinder 7 is P0207, the misfire code P0307.
- What you may notice
- Check engine light on
- Misfire on cylinder 7, on the LT5 mostly under high load
- Reduced power at full throttle
- Likely causes
- LikelyOpen winding in the cylinder 7 port injector
- PossibleBroken wire or terminal in the port injector harness of that bank
- RareSeparate fuel injection control module faulty (GM LT5)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €100 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.