P0207

Code P0207 means the engine control module (ECM) has identified an electrical malfunction in the fuel injector circuit for cylinder 7. This code only applies to engines with seven or more cylinders — predominantly V8 engines, though it can also appear on V10 and V12 configurations. The ECM has determined that the circuit controlling cylinder 7's injector is not functioning within its expected electrical parameters.

On a V8 engine, cylinder 7 is usually located toward the rear of one bank, making it one of the more difficult cylinders to access. You'll notice the engine running rough, with reduced power that's most apparent during acceleration or when the engine is under load. The misfire may cause slight hesitation and an uneven exhaust note. On a V8, losing one cylinder is about a 12.5% power loss, which is noticeable but less dramatic than on smaller engines.

Because of cylinder 7's typically rearward position on V8 engines, both diagnosis and repair tend to require more time and effort. The wiring harness in this area runs near exhaust components and is especially susceptible to heat damage. Professional repair costs are slightly higher for rear cylinders due to accessibility challenges. If you're attempting a DIY repair, be prepared to work in tight spaces and potentially remove intake manifold components for access.

Severity

Symptoms

• •Check Engine light is on
• •Engine runs rough with noticeable misfire
• •Reduced power especially under load
• •Poor fuel economy
• •Engine vibration at idle and low speeds
• •Possible rough exhaust sound

Likely Causes

Estimated Cost

Common Fixes

1. Replace the cylinder 7 fuel injector
2. Repair or replace damaged injector wiring
3. Clean or replace corroded injector connector
4. Verify ECM output and replace if driver circuit has failed

Shop Parts

Related Codes