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Tom, ASE Certified Technician
Category: Lexus
Satisfied Customers: 25954
Experience:  ASE Certified Master Technician qualified to work on all makes and models.
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My 2003 ES300 will not idle anymore. I replaced the Battery

Resolved Question:

My 2003 ES300 will not idle anymore. I replaced the Battery and cleaned up (Corrosion)the Connecting cables. The car still will not run unless the gas pedal is pushed. A friend suggested the Mass Air Flow Sensor might be bad. I just replaced the car is worse. The Check Engine light is on and the "Trac off" and "VSC" indicators are on solid.

I had to leave the old Sensor at the parts place. So I can't put it back in the car.

When I start the car.....the engine used to idle at about 200RPM's (Way down from normal) Is this a case where the "new" sensor must be Programmed into/by the computer?

Any suggestions would be appriciated.


Bob in Philadelphia
Submitted: 7 years ago.
Category: Lexus
Expert:  Tom replied 7 years ago.
No the new sensor you got was bad and the old sensor was good .SO return that sensor and get you old one back an install it .Then disconnect the battery and clean out the throttle body and throttle plate then reconnect the battery and see if it idles which it should.The new mass air flow sensor is definitely bad so give it back and get your old one back thats not the issue.It does not need to be programmed.This is the next sep let me know how it goes.

Positive feedback and bonsues greatly appreciated.
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