Q: Check Engine light; catalytic converters failing

asked by on January 30, 2016

The Check Engine Light came on. Two codes came up saying two of the four catalytic converters are failing. This caused my truck to fail a smog test. I noticed my coolant overflow kept draining down to nothing after I filled it, but I don't see a leak.

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.

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