Running lean or rough idle: simple checks before parts swapping

Overview

Before you replace injectors or a fuel pressure regulator, check the cheap stuff. A vacuum leak, dirty IAC, or sensor giving bad data causes the same codes and symptoms as a fuel system problem. Run through this list first. Most lean-running and rough idle complaints on a Cherokee trace back to something free or cheap to fix.

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

• CherokeeForum: Running lean and rough idle
• NAXJA: Rough idle and running lean discussion

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