engine missing out @ high rpms HELP have codes

MSTANG said:

Plugs

Serious check the gap they may be too worn...could be too lean or fat at that RPM range... could be the SPW... look at the plugs it'll narrow it down for you

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jrichker said:

Code 12 -Idle Air Bypass motor not controlling idle properly (generally idle too low) - IAB dirty or not working. Take it off and clean it thoroughly with throttle body cleaner. Clean the electrical contacts at the same time.

CODE: 31 (KOEO) - EVP circuit below minimum voltage. Vref missing or broken wire or bad contact in circuit. Check for 5 volts on the orange/white wire. With the sensor removed from the EGR and still connected, press the plunger and watch the voltage change on the brown/lt green wire. Check for the same results on pin 27 on the computer.

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