» » »

Nissan Q&A

Ask Your Question

2006 Nissan Xterra Question: flashing Service Engine Soon light on highway

 

Question

lilcezar, Austin, TX, February 20, 2011, 11:06
 Rookie

During long 8 hour freeway drive, "Service Engine Soon" light flashed when I passed or exceeded 2.5k RPM. As long as I did not exceed that RPM, or go up hills, the light remained off. Is this "trani" related or "cat" emmissions related? Both front cats replaced Dec. 2010. I also replaced plugs with the "Pulstar" capacitor plugs. Are my cats going to burn up?

2 Answers
Flag This
  • Answer #1

    patrick mannion from Greg Solow's Engine Room, February 20, 2011, 15:31
    Profile_thumbnail
     Master

    Flashing check engine light is serious. If the Check Engine Light/Service Engine Soon light illuminates while you are driving, the car's on board computer sees a fault in the engines management system that is causing an excess amount of pollutants to be emitted from your car. This could result in engine damage if left neglected. Some problems that can cause the Check Engine light to stay on may take two "drive cycles' to complete before illuminating the Check Engine Light. The computer sees a problem and looks for an identical set of circumstances to occur to confirm that it has indeed seen a problem before turning on the light. A Check Engine light that continually flashes while you are driving is serious and is a sign that the computer sees a problem that seriously risks damaging the catalytic converter which may result in an expensive repair or even may cause a fire! Diagnostic codes are stored in the vehicle's computer and can be retrieved using a scantool that communicates with the computer in your car. We have in our Repairpal website an encyclopedia with in depth articles about computer, and computer control systems, emission and driveability problems. http://repairpal.com/check-engine-light

    Flag This
  • Reply

    lilcezar, February 20, 2011, 15:46
     Rookie

    Thanks for the heads up. I checked plug connections after codes indicated plug #5 missfire. #5 was loose. Cleared codes and runs like new.

    Reply
    Flag This
  • Answer #2

    daveer (see my shops), February 20, 2011, 15:33
    Profile_thumbnail
     Technician

    A flashing check engine light means that the computer is sensing something is possibly damaging the cats. Usually caused by an engine misfire. That fits the rpm and uphill portion of your symptom as well.

    Flag This
  • Reply

    lilcezar, February 20, 2011, 15:46
     Rookie

    Thanks for the heads up. I checked plug connections after codes indicated plug #5 missfire. #5 was loose. Cleared codes and runs like new.

    Reply
    Flag This