Injector Circuit / Open — Cylinder 2
The DURAMAX-P0202 (Duramax) diesel fault code means: Injector Circuit / Open — Cylinder 2. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $400-$900 per injector (LB7 often needs all 8 done; $3,000-$5,500 total)
Down with a Duramax fault on the road?
Get connected with a verified mobile diesel mechanic near you. Verified diesel & reefer techs, launching on the freight corridor.
Find a mobile mechanic →A $30 car code reader can't do diesel. The HD7000 reads full-system codes and does parked DPF regen, idle/speed-limit, and service resets from the cab — on everything from a 6.7 Cummins/Power Stroke/Duramax pickup to Class-8 trucks (Detroit, Paccar, CAT, Volvo, Mack, International).
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Full-system 6/9/16-pin diesel scan tool for Cummins, Paccar, CAT, Detroit and more — plug-and-play, no subscription. A cheaper way to read heavy-duty codes a basic OBD2 scanner skips entirely.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Common Symptoms
- Rough idle or misfire at idle
- White or black smoke from exhaust
- Reduced power / limp mode
- Hard starting or long cranking
- Check Engine Light illuminated
Probable Causes (Ranked by Likelihood)
- Failed injector solenoid on cylinder 2 (LB7 notorious for this) Very Likely
- Open or damaged injector harness wiring to cylinder 2 Likely
- Corroded valve cover pass-through connector (LB7 under-valve-cover harness) Likely
- FICM or injector driver module fault Possible
Step-by-Step Diagnostic Procedure
Scan for balance rates on all 8 cylinders; cylinder 2 balance outside ±4 mm³ confirms injector issue
Remove valve cover and inspect under-valve-cover harness for fuel saturation (classic LB7 failure)
Measure injector solenoid resistance at ECM side — should be ~0.5-2.0 ohms. Open indicates injector or harness fault
Back-probe the injector connector at the valve cover pass-through and repeat test to isolate harness vs. injector
Replace faulty injector and re-learn balance rates with Tech 2 or equivalent scan tool
Frequently Asked Questions
What is P0202 on a Duramax?
Duramax code P0202 (Injector Circuit Open — Cylinder 2) is a serious-severity diagnostic trouble code triggered by the engine control module when it detects a problem in the associated system. On LB7 Duramax engines (2001-2004) this code is almost always caused by cracked injector solenoid balls — a GM service campaign covered some of them but not all.
Is a Duramax P0202 safe to drive?
Yes, briefly. You can drive short distances at low load to reach a shop, but extended operation with a dead cylinder can wash down the cylinder wall with diesel fuel, diluting the oil and damaging bearings.
How much does it cost to fix P0202 on a Duramax?
Individual injector replacement runs $400-$900 parts and labor. On LB7 engines, dealers and indies almost always recommend replacing all 8 injectors at once, bringing the bill to $3,000-$5,500. The job requires removing the valve covers and the injector hold-downs.
P0202 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: