Q: My GMC safari van misfires on the freeway or when I go faster than 65 mph then the check engine light comes on steady for 15 minutes

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My check engine light comes on steady for a short period, maybe 15 minutes or so then it starts flashing off and on. The van starts pulling back first when I go faster than 65 mph. I just had the starter replaced and the rotor cap.
My car has an automatic transmission.

Hello - first task is to determine what problem codes are being set which are turning on the Check Engine light. Most auto parts stores will read these for you for free. This problem could be weak ignition (old plugs, bad plug wires, weak coil and/or ignition module). It could also be a poor fuel supply issue - clogged fuel filter, failing fuel pump, weak fuel pressure regulator or fuel pump relay with burned contacts (poor current supply to the fuel pump). The problem codes will save time and money by directing repairs! I would recommend you have an inspection for the engine misfire to be completed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

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