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Q: OBD-II scanner read code P0108

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After reading the code on the OBD II auto scanner as P0108, I replaced the MAP sensor. After that I reset the code after installing new one. I continued by testing the OEM on the old one, plus the new one, and they both read 1 per OEMs meter. They are both looking good, however it did not fix the problem. The service engine light is still coming on, plus the same code, P0108 is also still shows. To explain more details, the service light had not come on immediately. I had cleared the code and then I turned the ignitions switch to On; however, I did not start my car. After waiting for 10 seconds, then I turned the ignition switch off again. After plugging in the OBD2 scan tool, I scanned for codes but there were none. After turning off the car, the code P0108 appeared once more. It does not seem that the ECM will be going out. Please give me your advice as to what I should do. Thanks.

A: Hello. The MAP sensor reading on a scanner ...

Hello. The MAP sensor reading on a scanner should read about 1.0 to 1.5 volts at idle and 4.5 to 4.8 volts at wide open throttle. The MAP should read 4.8 volts or more when you have the key on engine off. If either sensor is not within these specs, then replace have it replaced. Once you install the sensor, then clear the codes and road test the vehicle to see if code returns. If it returns, then you will need to have the entire pinpoint test done to check the wiring and ECM for problems.

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