Q: Many issues with the car. Can a clogged catalytic converter cause transmission issues?

asked by on October 24, 2016

I got this car in June, for free, it was passed from my great grandmother who very rarely drove it, to my uncle, then my parents, then to me. Which meant, I got to deal with all the problems nobody fixed before. I just recently replaced the alternator, belt tensioner, and terminals. The car drove fine for a couple weeks, and out of nowhere decided it didn't want to accelerate past 10/mph after stopping. Figured it was the brakes, went easier on them when coming to a stop, it drove fine for about 3 days. Then all of a sudden my car is extremely loud, and shakes alot while driving, not just when stopped. My dad said my catalytic converter is clogged. Tonight, my o/d off light came on, I noticed it after my car started jolting forward when it would shift into the next gear. I knew automatically it was the transmission messing up. Can a clogged catalytic converter cause these issues with the transmission? I didn't have these issues until this happened all together recently.

My car has 169000 miles.
My car has an automatic transmission.

The catalytic converter has very very little to do with the transmission. The catalytic converter will keep the engine from being able to "exhale" and can cause engine problems and damage if faulty, but it wont cause direct transmission issues. All it does it turn exhaust fumes to other elements that are safer for the environment. The very first step is to get the vehicle scanned for diagnostic troubleshooting codes. Since warning lights have illuminated, the computer may have detected an issue which will help with this diagnosis. The transmission will need to be inspected. The first step is to remove the fluid pan and filter. Here you can check the condition of the oil and filter. You can also check the pan for metal shavings which could be a sign of bigger issues. The transmission fluid may have never been changed or serviced and you will want to make sure its clean. If you would like to have these symptoms addressed, a certified technician from YourMechanic can come to your location to diagnose the loss of power and shaking issues in person so that the correct repairs can be done.

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