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Q: Engine light and throttle body light come on every morning when first start

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I installed a crate engine and drove for about 700 miles with no issues and then I had the a/c recharged from having replace the engine. The next day I started it in the morning to go to work and the check engine and throttle body lights came on, I have a handheld scanner and it said MAP sensor P0108. So I replace the map sensor and the next day same thing when I started it. Same code P0108 map sensor, so then I took it to a local shop and had them hook it to there computer and they got same thing. So I replaced the map sensor again and same thing happen the next morning, so I took it back and the scan it and said I need to replace the throttle body. So I did and reset it to what the manual said and the next morning yep same thing, so then I took it to the dealer to have them check it and they had know idea. So 170.00 dollars later I took it back home, I check all wiring and connector's could not find nothing wrong except the air charge temp sensor was broken so I replaced it.

My car has 202700 miles.
My car has an automatic transmission.

A: Hi there. Check the Manifold Absolute Pres...

Hi there. Check the Manifold Absolute Pressure (MAP) sensor voltage. Key on engine off it should be approximately 4.5 volts, idling in the 1 volt range and go over 4 volts at a snap throttle. Then, check the Throttle Position Sensor (TPS) voltage in the pedal follower test with the scan tool. At closed throttle TPS #1 should be approximately 0.5 volt and at Wide Open Throttle (WOT) over 4 volts. TPS #2 should read 4.5 volts closed and 0.5 volt at WOT. If everything is working correctly, then you will need to have your engine control module (ECM) flashed (reprogrammed) to match the crate motor. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, that can assist you with your vehicle.

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