1998 Mitsubishi Eclipse Running too lean

Tiny
COREYMITCHELL
  • MEMBER
  • 1998 MITSUBISHI ECLIPSE
  • 4 CYL
  • FWD
  • MANUAL
  • 15,800 MILES
I installed new headers and downpipe on my 98 eclipse and the check engine light came on and said "system running lean" plus when I try to maintain a certian speed like "55" it acts like it is starving for fuel (bucking and sputtering) but only when I am giving it little throttle when I am picking up speed its fine what to do?
Tuesday, July 28th, 2009 AT 10:17 PM

1 Reply

Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
1998 Mitsubishi Eclipse Running too lean

A lean fuel condition can be caused by:

* Low fuel pressure due to a weak pump or leaky fuel pressure regulator. (Use a fuel pressure gauge to check fuel pressure at idle)

* Dirty fuel injectors. (Try cleaning the injectors)

* Vacuum leaks at the intake manifold, vacuum hose connections or throttle body. (Use a vacuum gauge to check for low intake vacuum)

* Leaky EGR valve. (Check operation of EGR valve)

* Leaky PCV Valve or hose. (Check valve and hose connections)

* Dirty or defective Mass Airflow Sensor (MAF). (Try cleaning the MAF sensor wires or filament with aerosol electronics cleaner. Do NOT use anything else to clean the sensor, and do not touch the sensor wires
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Tuesday, July 28th, 2009 AT 10:23 PM

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