Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit/System Testing: P0641
2006 Buick Allure CXSSECTION P0641
WARNING: This page is about a different variant/trim than selected.
- With the ignition OFF, disconnect the harness connector at the MAP sensor.
- With the ignition ON, measure for 4.8-5.2 volts between the MAP sensor 5-volt reference circuit and ground.
- Command the EGR valve to 100 percent while monitoring the MAP sensor 5-volt reference circuit with a DMM.
- If within 4.8-5.2 volts, refer to Testing for Intermittent Conditions and Poor Connections .
- With the ignition OFF, disconnect the harness connector at the EGR valve.
- With the ignition ON, measure EGR valve 5-volt reference circuit.
- If within 4.8-5.2 volts, replace the EGR valve.
- If over 5.2 volts, check for unexpected voltage at each 5-volt reference circuit or the signal circuit for each component associated with the 5-volt reference.
- If under 4.8 volts, check for a short to ground or low reference circuit at each 5-volt reference circuit.
- With the ignition ON, use a scan tool to observe the voltage parameter for each component associated with the 5-volt reference circuit while disconnecting each component one at a time.
- If the data parameters change with any component being disconnected, replace the component.
- If all circuits tested are OK, replace the control module.
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:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.