Idle HC/Co Concentration Check

2000 Saturn SL2 Automatic, MP6SECTION Idle HC/Co Concentration Check
NOTE: This check is used only to assist with idle HC/CO Diagnostics.
  • Initial Conditions:
    • Engine must reach normal operating temperature.
    • Air cleaner installed.
    • All pipes and hoses of air induction system connected.
    • All vacuum lines properly connected.
    • All fuel system wiring connections fully plugged.
    • Transmission in P (Park) or N (Neutral) range.
    • Tachometer and HC/CO meter calibrated and in hand.
  • Run engine at 2500 RPM for approximately 2 minutes.
  • Insert HC/CO meter testing probe into intermediate pipe at least 40 cm (16 in).
  • Check HC/CO concentration at idle.
NOTE: Wait at least 1 minute before measuring to allow the concentration to stabilize. Complete the measuring within 3 minutes. If the HC/CO concentration does not conform, see the following HC/CO diagnostic chart for possible causes. See Figure
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.