P0290: Cylinder 10 is not contributing as much power as the others
Cylinder 10 contribution/balance fault
Severity: Severity not verified — if the car runs badly, have it inspected
Loss of power or misfire is possible, so have it checked.
P0290 in short
P0290 means the engine computer found that cylinder 10 is not contributing equally to engine power. TroubleCodes.net says dirty injectors are the most common cause, followed by a wrong injector fitting procedure or mechanical wear. It only applies to engines with ten or more cylinders.
The computer compares how much each cylinder adds to engine speed. When cylinder 10 lags behind the rest, it sets P0290.
TroubleCodes.net names dirty fuel injectors as the most common cause. It also lists injectors fitted without the learning procedure diesel engines need, and mechanical faults such as burnt valves, worn rings or a leaking head gasket.
Most likely causes
These are general causes for this code across vehicles. None is specific to one make or model.
Cause 1: Dirty or faulty fuel injector on this cylinder
Possible — needs testing- Why it ranks here
- Listed first by TroubleCodes.net as the most common cause.
- What would change this
- Rises if the injector's waveform or sound differs from its neighbours.
Cause 2: Injector replaced without the learning procedure
Possible — needs testing- Why it ranks here
- TroubleCodes.net says diesel injectors need a learning procedure after installation.
- What would change this
- Rises if the code began after an injector was changed.
Cause 3: Mechanical fault in the cylinder (valves, rings, head gasket)
Possible — needs testing- Why it ranks here
- Named by TroubleCodes.net after the injector causes.
- What would change this
- Rises if compression or leakdown differs by more than about 10 percent between cylinders.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Inspect the injector connector for corrosion or water damage.
IfCorrosion or damage is found
It meansRepair it and retest.
IfConnector is fine
It meansCompare the injector with its neighbours.
Step 2: Have a shop compare this injector's waveform or sound with the neighbouring cylinders, and run compression and leakdown tests.
Warning:Compression and leakdown testing involves cranking or pressurising the engine; leave it to a shop.
IfThis injector differs from its neighbours
It meansThe injector is the likely cause.
IfInjectors look alike but compression or leakdown varies
It meansThe problem is mechanical.
Points to: Mechanical fault in the cylinder (valves, rings, head gasket)
Symptoms
- Check engine light on
- Possible drop in fuel economy
- Rough idle or misfire in severe cases
How to fix
Step 1: Ask a shop to compare this cylinder with its neighbours before replacing injectors.
On your vehicle
We don't have reviewed vehicle-specific evidence for P0290 yet. The causes and tests above apply across vehicles.
Related codes
Sources and review
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
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