Rick's Free Auto Repair Advice

P1408 EGR out of self test range

Fix code P1408 EGR out of self test range

If you have a P1408 EGR out of self test range trouble code, this post will help you understand what it is and how to fix it.

Exhaust Gas Recirculation valves (EGR) open and close to allow exhaust gas to flow into the intake manifold. The computer commands to valve to open and close in varying amounts. But since this is a mechanical valve, the computer needs to check to make sure the valve actually opened the correct distance. Some manufacturers attach a sensor to the EGR to measure the distance. Other car makers actually watch the exhaust flow to see if it’s the right flow based on the commands to the EGR.

In this case, the computer has commanded the EGR valve to open fully and close fully so it can recalibrate. The readings it got are outside the acceptable limits.

© 2012 Rick Muscoplat

Posted on by Rick Muscoplat


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