It loses power sometimes at highway speed - the RPMs reduce and and then power returns. It happens more often when trying to accelerate from a stop sign. It is intermittent. I have installed new spark plugs and the only engine code I get is P1133.
My Ion is misfiring or losing power intermittently. on 2003 Saturn Ion
by jaybrunk in Minneapolis, MN on May 06, 2010
ANSWER by dandd on May 06, 2010
The P1133 is a slow reacting Oxygen Sensor, which may a result of the misfiring. If the engine is misfiring, are you getting misfire codes like PO300 or P0310 or P0302 etc. because, you should be. It may feel like a misfire, but is really something else. Try disconnecting your Oxygen Sensor and test driving the car for about 15 minutes. You may be experiencing a lean misfire from a defective Oxygen Sensor,. If the symptom changes or goes away, bingo. If not, take it to a shop for a Pro Diagnostic tech to figure it out. http://repairpal.com/directory?address=55417&car_brand_names=Saturn