How much money to invest in older camry for repairs?

What is your question?

400,000 + mi - love my car - hiway miles. Had to have it towed to shop after wouldn't accelerate and engine roughness noted. all maintenance done- never a major problem before this. What can I expect in future -or is it time to trade in? Can I expect that it can be fixed and I can continue driving? My kids want me to get new car but again, this has been the best car!