Q: Rattling noise in neutral. Car won't go over 30mph in 3rd.

asked by on December 16, 2015

I have a rattling noise coming from behind my skid plate (I think) while my car is in neutral. The engine starts up, and I can put it in gear. After I start driving, the engine doesn't have much power and once in third gear struggles to get up to 30 mph. What is wrong with my engine?

Hi thanks for the question, man, there is nothing worse than a car that won’t go anywhere when we want or need it to. It sounds like you may be having a problem with your catalyst converter in your exhaust. The rattling you’re describing could be a result of the core inside melting and breaking loose, causing the rattling you’re hearing, and also acting just like a plug in your exhaust pipe, so your engine can’t breath. Enlist the help of a mechanic who has the right test equipment to pinpoint the cause of your problem.

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