UK Car Repair Questions? Ask a Mechanic for Answers ASAP
When the issue occurs does the check engine light come on at all? Also, does it run rough like bucking or anything?
Alright, theres a couple things that I would suggest to begin. First off you should get it scanned for trouble codes, even though the engine light is not on, there still could be a code in the system that would give you a good idea of what direction to head. The only thing that rings a bell to me as a common problem would be the oil control valves that control the timing of the continuously variable valve timing. That would cause what you are describing. Do you change your oil regularly, and use a kia oil filter? If not, change the oil and use a Kia oil filter. If so, there is an inspection procedure that I have attached that you could do to check the valves.
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