1993 Lexus ES 300 6 cyl Front Wheel Drive Automatic 180000 miles
Hello. I have a 93 Lexus ES300 with about 180,000 miles. Before you groan, it is in pretty good shape; completely tuned up, new wires, etc. Recently it started having a problem idling. It would start ok, but you had to hold the gas pedal down a little or it would stall. Driveability was ok otherwise. It has worsened to where now if you are driving along and take your foot off of the gas it will stall out. I readjusted the throttle stop screw, no change. I took apart the IAC valve and cleaned it and lubed the motor. Tested it and it works fine. No change. The codes 24 and 31 (Intake air temp and MAS) keep coming on. I have tested ECM voltages and resistances of the sensors and they all seem to check fine. Please help. It is my daughter's boyfriend's car and she is starting to give me a hard time about it! Thanks.
I would lean toward the MAF being the problem. Try cleaning out the throttle bore around the butterfly with carb cleaner and a rag. Check for vacuum leaks and cracks in the air intake boot between the MAF and the engine. You can try some MAF cleaner for a short term to see if it helps but I have never had much luck with it lasting very long
February, 6, 2008 AT 8:33 PM
Thank you very much for your help. One last related question. I am not sure, but I believe that the Intake air temp sensor is seperate from the MAS on this car. Is it actually a seperate item, and should I replace it also since code 24 was set? Thanks very much again.
February, 7, 2008 AT 7:29 AM
Try the MAF first and clear the codes to see if the IAT code comes back