What is MID 90 & How to Solve It?

What is MID 90:

MID 90 refers to an issue with the Exhaust Gas Recirculation (EGR) System. The ECM detects a malfunction in the EGR system, which can affect exhaust gas flow regulation and lead to poor engine performance, increased emissions, and potential engine stalling.

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Why This Happens:

• Faulty EGR valve.
  
• Shorted or damaged wiring in the EGR control circuit.
  
• Blocked or contaminated exhaust system components.
  
• Loose or corroded connectors.
  
• ECM failure to process EGR data.
  
  

How to Fix It:

1. Inspect the EGR valve and wiring for visible damage or malfunction.
   
2. Test the EGR valve to ensure proper operation.
   
3. Clean or replace the exhaust system components as needed.
   
4. Replace the faulty EGR valve if necessary.
   
5. Ensure proper communication between ECM and EGR control circuit.
   
   

How to Avoid It Before It Happens:

• Regularly inspect the EGR valve and wiring.
  
• Keep the exhaust system clean and free from blockages.
  
• Perform routine maintenance on the EGR system.
  
• Use diagnostic tools to monitor EGR performance.
  
• Clue’s equipment maintenance services monitor EGR systems to prevent issues before they affect engine performance.