Can a bad catalytic converter cause head gasket failure?
Running a vehicle with a bad catalytic converter over thousands of miles leaves drivers questioning whether the added engine stress triggers head gasket failure or if the issue is simply age-related. Drivers also encounter related hardware problems, such as finding iron particles accumulating in the intercooler.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Replacing the failed turbocharger unit
- 2Asking online forums for diagnostic opinions and mechanical advice
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Yeah, I got that one haha. That will definitely not go back. I even have iron in the intercooler :)”source ↗
“I’ve been running my 2005 Subaru Outback for the last year (~25,000 miles) with a bad cat. A couple months ago (~5,000 miles) my head gasket started to fail.”source ↗
“Wonder if running the car with a bad cat stressed the engine and caused the head gasket to fail. Or if it is just age related.”source ↗
Where this came up
People with this problem also raised
- 2Why is my new turbocharger screaming after a few hundred miles?
- 35Why does my car make a loud rattle when starting the engine?
- 10Engine misfires and RPM surging when driving uphill
- 5Why is one coil pack tube hotter than the others?
- 3How to diagnose transmission clunking and slipping before replacing it
- 5Why is my truck shaking and popping after replacing wheel hubs?