P22DD code meaning
Cylinder 2 Alternative Fuel Injector Control Circuit/Open
Powertrain system Generic code P22xx codes Check engine light
What P22DD means
P22DD signals an interruption in the circuit of the cylinder 2 gas injector. On many systems that circuit is not driven by the engine computer: Ford's 2003 bi-fuel CNG trucks used a separate alternative fuel control module holding drivers for both injector sets, with heavier stages for the gas injectors because they draw more current. GM's 2014 bi-fuel Silverado likewise stores gas faults in its own CNG control module (bulletin PIP5181), so a scan tool has to read that module as well. No maker documents P22DD publicly; TransEco and Ford list only the cylinder 2 Low/High codes P22DE and P22DF, and TransEco assigns an open line to Low. Look for a burnt coil or a separated connector before blaming the module.
P22DD at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P22DD
- Malfunction indicator lamp on
- Gas mode not available or ends shortly after switching
- Misfire on cylinder 2 when running on gas
Common causes of P22DD
- Most likelyBurnt-out or open coil in the cylinder 2 gas injector
- PossibleConnector at the cylinder 2 injector loose or pulled off
- PossibleWire break between gas control module and injector
- Less likelyFailed injector driver in the separate gas control module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Alternative fuel injector
What each part of P22DD means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 2 | Area: fuel and air metering (injector circuit). |
| DD | The exact fault in that area. |
What to do next
- Note P22DD and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P22DD
What does P22DD mean?
P22DD means "Cylinder 2 Alternative Fuel Injector Control Circuit/Open". P22DD signals an interruption in the circuit of the cylinder 2 gas injector. It is a generic code, so it means the same on every make.
Is it safe to drive with P22DD?
Drive gently and only to a workshop. With P22DD the car can go into limp mode (reduced power) to protect itself.
Will P22DD fail an emissions test?
Yes, it can. P22DD is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P22DD to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P22DD clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.