Engine Vacuum Leak Detected (Ford)
What does P1190 mean?
The P1190 code means the vehicle's onboard diagnostic system has detected: Engine Vacuum Leak Detected (Ford). This is a moderate severity code.
Common Symptoms
- Check Engine Light on
- Rough or high idle
- Hissing sound from engine bay
- Poor fuel economy
- Engine surging or hunting at idle
Probable Causes (Ranked by Likelihood)
- Cracked or disconnected vacuum hose Very High
- Intake manifold gasket leak High
- PCV valve or hose failure Moderate
- Brake booster vacuum hose leak Moderate
- Cracked intake manifold Low
Step-by-Step Diagnostic Procedure
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Visually inspect all vacuum hoses for cracks, splits, or disconnections
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Perform a smoke test to pinpoint the exact leak location
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Check the PCV valve and hose for cracks or blockage
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Inspect the intake manifold gasket area for signs of leaking
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Check the brake booster hose and check valve
Frequently Asked Questions
What is a vacuum leak?
A vacuum leak is an unwanted opening in the intake system that allows unmetered air to enter the engine. This extra air leans out the air-fuel mixture, causing rough idle, poor performance, and increased emissions.
How does a smoke test work?
A smoke machine pumps theatrical smoke into the intake system with the engine off. The smoke exits through any cracks or gaps, making leaks visible. This is the most effective way to find vacuum leaks.
Can a vacuum leak cause engine damage?
A small vacuum leak will not cause immediate damage but will reduce efficiency and increase emissions. A large vacuum leak can cause a severe lean condition that may damage the engine or catalytic converter over time.