Honda Repair Questions? Ask a Mechanic for Answers ASAP
If the clutch has been replaced and the transmision is still popping out of gear I feel that you have some worn synchronizers in the transmission that are causing this. When those synchro's wear out prematurely they do not have the strength to properly hold the transmission in gear. I know they have assured you that the gearbox/trans is not the problem but I feel from your description that it is causing your issue. As for the Check Engine Light I would need a code to know exactly what is causing that light to come on. Let me know if you have any other questions and I will be glad to help. Please remember to rate me at Excellent Service and Thank You for letting me assist you today!