Q: Check Engine light; catalytic converters failing

Hi there. It sounds like you have a few issues going on here. If the catalytic converters are failing, then the converters will need to be replaced. They tend to either fail and become clogged causing a loss of engine power, or they simply fail and no longer react as they should. As for the loss of coolant, this engine has a history of head gasket failures even if the engine has never gotten hot. Most of the time this occurs on the driver side of the engine. A block test will reveal the problem area, but many times I’ve had to use a bore scope to look inside of the cylinders to find where the coolant is going. It is typically the rear cylinder on the driver side. If you need further assistance, a certified mechanic, like one from YourMechanic, will be able to diagnose the coolant issue.