Vacuum gauge test for exhaust restriction (simple driveway test)

Overview

A clogged catalytic converter robs power and can cause the engine to run hot. Before you buy a new cat or disconnect the exhaust to test it, a vacuum gauge at the intake manifold at idle and under light throttle will tell you if there's backpressure. It's a 10-minute test that can save you from an unnecessary exhaust job.

What you need

• Basic hand tools
• Flashlight
• Optional: multimeter

Quick checks first

1. Quick check 1
2. Quick check 2
3. Quick check 3

Step-by-step

1. Step 1
2. Step 2
3. Step 3

If that did not fix it

• Next likely cause 1
• Next likely cause 2

Source links

• Cruiser54: Vacuum test for exhaust restriction

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