P0270Fuel & Air Metering

Cylinder 4 Injector Circuit Low

P0270 means the ECM detected a low voltage condition in the cylinder 4 injector circuit. Common causes are a short to ground, a failed injector, or wiring problems.

🚗 Risky. An injector circuit fault on cylinder 4 causes a misfire and can harm the catalytic converter. Diagnose promptly.
HIGH
severity
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🎯 Top Causes, Ranked by Likelihood

#1Short to ground in wiring$50-$300
40%
A grounded control wire pulls the circuit low.
#2Failed cylinder 4 injector$100-$500
30%
An internally shorted injector.
#3ECM injector driver fault$200-$1000
15%
A failed driver for cylinder 4.

🩺 Common Symptoms

💰 Repair Cost: DIY vs Shop

DIY Cost
$50-$500
Shop Cost
$150-$1000

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P0270

1Inspect the cylinder 4 injector wiring for shorts
2Measure injector 4 coil resistance
3Swap injector to another cylinder to test
4Test the injector 4 driver circuit

❓ Frequently Asked Questions

Can I drive with P0270?
Only briefly. An injector fault causes a misfire and can harm the catalytic converter. Diagnose promptly.
What is the most common cause of P0270?
A short to ground in the wiring or a shorted injector are the most common causes.
How much does P0270 cost to fix?
Wiring repairs are cheap; an injector often runs $100-$500 including labor.

🔗 Related Codes

P0271P0204P0267P0261
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