Q: Hesitation between 40 & 50 mph.

asked by on December 16, 2016

I have a 2003 Ford Crown Victoria & whenever driving there is a hesitation between 40 & 50 mph, during acceleration & I experience it while maintaining a speed between 40 & 50, once past 50 or below 40 there are no issues... What can cause this?

My car has 110000 miles.
My car has an automatic transmission.

After scanning the computer for codes to see if there is codes for the transmission or EGR system. If no codes then you should disconnect the EGR vacuum control valve and road test to see if problem of surge continues. If problem continues then the transmission pressures would need to be tested for a possible pressure control valve problem in the transmission or the overdrive solenoid or the torque converter is not locking up and need replaced.

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