P2B01 code meaning
Cylinder 2 Injection Pulse Performance
Powertrain system Generic code P2Bxx codes Check engine light
What P2B01 means
P2B01 is stored when the ECM keeps missing the opening signature of the cylinder 2 injector in normal running, i.e. it has no proof that fuel was delivered on that cylinder's commanded pulses. GM uses the code on direct-injection gasoline engines. The 2019 table for the 2.7 L L3B judges 100 failures out of 380 samples; the 2025 tables reach a verdict sooner, after 50 to 100 samples. Both are Type B with the warning lamp on the second trip. GM's preliminary information PIT5677 to PIT5677E for 2019–2021 Silverado and Sierra 1500 with the L3B lists P2B01 next to P2B00 and P2B03 among dozens of codes that a grounded, chafed engine harness can trigger. A misfire count on cylinder 2 (P0302) helps tell an injector problem from a wiring one; P2B09 is the cold-start version.
P2B01 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.3 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P2B01
- Warning lamp after two trips
- Uneven idle, possibly misfire on cylinder 2
- Together with many other codes and erratic behaviour when the harness is shorted
Common causes of P2B01
- Most likelyEngine harness shorted to ground at a chafe point (GM L3B bulletin series PIT5677)
- PossibleCylinder 2 injector opening sluggishly or not at all (deposits, worn armature)
- Less likelyCorroded or loose injector 2 connector distorting the feedback voltage
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel injector cylinder 2Injector wiringEngine control module
What each part of P2B01 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| B | Area: hybrid propulsion. |
| 01 | The exact fault in that area. |
What to do next
- Note P2B01 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 P2B01
What does P2B01 mean?
P2B01 means "Cylinder 2 Injection Pulse Performance". P2B01 is stored when the ECM keeps missing the opening signature of the cylinder 2 injector in normal running, i.e. It is a generic code, so it means the same on every make.
Is it safe to drive with P2B01?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2B01 fail an emissions test?
Yes, it can. P2B01 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 P2B01 to fix?
Difficulty: medium. A typical repair takes 0.3 to 4 hours of work. This is a job for a workshop.
Will P2B01 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.