Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means the car's computer thinks there's not enough air going into the engine when it's idling. It's like when you're trying to breathe through a straw that's too small.
The engine control module (ECM) detects that the amount of air entering the engine at idle is less than expected.
The P1102 code is triggered when the ECM detects that the adaptation of the unmetered air mass at idle is below the specified range. This could be due to a malfunction in the idle air control system or a problem with the air intake system.
• Rough idle
• Stalling at idle
• Check Engine Light illuminated
• Faulty idle air control valve
• Vacuum leak in the intake system
• Dirty or clogged air filter
ECM: Engine Control Module
Idle Air Control Valve: A component that regulates the amount of air entering the engine at idle.
• Check for vacuum leaks in the intake system.
• Inspect the idle air control valve for proper operation.
• Examine the air filter for dirt or obstructions.
• Replace or clean the idle air control valve.
• Repair any vacuum leaks found in the intake system.
• Replace the air filter if it is dirty or clogged.
• OBD-II scanner
• Vacuum gauge
• Screwdriver set
$100 - $300
Moderate
• Ford Focus
• Mazda 3
• Volkswagen Jetta
• Regularly replace the air filter.
• Perform routine maintenance checks for vacuum leaks.
• Keep the throttle body clean.
Engine Performance
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid driving the vehicle if it stalls frequently at idle.
Check with your vehicle manufacturer for warranty coverage on engine components.
The P1102 code has been associated with idle control issues in various vehicles, particularly those with higher mileage.
Moderate – Addressing this issue can prevent stalling and improve engine performance.
Driving with this code may lead to unsafe stalling conditions. Address promptly to ensure safe operation.
• Engine at operating temperature
• Vehicle at idle
The idle air control valve is typically located on or near the throttle body of the engine.
Q: Can I drive my car with a P1102 code?
A: It's not recommended as it may cause stalling and unsafe driving conditions.
Q: How can I prevent a P1102 code from occurring?
A: Regular maintenance, including air filter replacement and checking for vacuum leaks, can help prevent this code.
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