P0638

Throttle Actuator Control Range/Performance (Bank 1)

Severity: High Fuel & Air Metering Generic OBD-II Code Est. Repair: $200 - $600

High severity. Avoid long drives and get diagnosed as soon as possible. Flashing check engine light = stop driving if safe.

Quick Answer

P0638 means “Throttle Actuator Control Range/Performance (Bank 1).” Severity: High. Estimated repair cost: $200 - $600. Most common sign: Reduced power/limp mode.

What Does P0638 Mean?

Electronic throttle body's actual position doesn't match the commanded position.

Common Symptoms

Reduced power/limp mode
CEL
Hesitation

Possible Causes

Carbon buildup in throttle body
Faulty throttle actuator motor
Faulty TPS
Wiring issue

How to Fix P0638 – Repair Guide

Clean throttle body
Test actuator and TPS
Replace throttle body assembly if faulty
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Budgeting for This Repair?

A typical P0638 repair runs about $200 - $600. If you'd rather spread the cost over time, estimate the payment with our free sister tool: Car Finance Calculator (50-state sales tax, trade-in equity, full amortization).

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Disclaimer: Information is for educational reference only and does not replace professional diagnosis. Actual causes and costs vary by vehicle make, model, year and condition. Always verify with a qualified technician.