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Possible transmission or engine problem engine code P0107

for the last week or so when I am driving my car it will suddenly jerk and slow down and not want to speed back up. the jerking feels like the transmission is slipping and the check engine light came on once. I had my transmission looked at and they didn’t see any problems physically however there was metal and gunk built up around the lid for the transmission fluid. They flushed the transmission fluid and that did not help. After they flushed the transmission fluid they told me to drive it for a few days and see what happened. The next day my car jerked so hard that I hit my face on the steering wheel and my car went from 55mph to 35mph. I got the engine code which is P0107, what is going on?

Trouble code P0107 indicates a problem related to the Manifold Absolute Pressure sensor (MAP).
When there is a problem of this type, you can experience difficulty in starting, and/or you can have a very rough-running engine. Gas mileage can also drop off badly.

However, before you replace the MAP sensor, make sure that you check all of its wiring and its wire connectors. Corrosion on the connectors, or damaged insulation on the wire leading to the MAP sensor, can produce the same trouble code.

In addition to checking the wiring and such the MAP sensor itself can be tested. If you don’t mess with cars at all you’d ask a shop to test it. If you do mess with cars $20 a repair manual will give you the procedure and specs for at least a basic check of the sensor.

When the car jerks and slows does the engine rev up really high as if it just downshifted? I don’t know the Elantra’s transmission controls (and I couldn’t try to find out since you never even gave the year of the car), but the MAP sensor is sometimes an important input for computerized transmission control. It is part of how the computer “knows” about changes to engine load.

The model year, model, engine, and mileage is always helpful…