Smells like it's burning.

So I have a 1997 2.4L 4cylinder with about 265k miles on it. Now I was driving around town the other day when my muffler rusted right off of my truck... So I got a new one and replaced it.

Now a few days later my CEL comes on and there's a burning smell. My obd2 reader wouldn't read the code until the next day. Gave me the ol' P0420. So I'm thinking "Okay, that burning smell must've been someone else." So I clear the code.

Today I'm driving around and the CEL comes back on and my reader hasn't been able to tell me what it is. But I smell that burning smell again and this time I'm the only car around so there's only one option there. I'm assuming that the code is another P0420. And on top of that my engine won't power on through 1st and 2nd gear without some strange sputtering. I have to give 1st a lot more power than it needs to keep the engine from shaking violently, and since the roads are wet here lately I'm spinning my tires since it's only RWD.

Any ideas as to what the problem and solution might be? I thought I'd ask yall before going to a dealership or shop. I like to solve most of the problems myself.

 

Bump for really needing answers.

 

maybe your cat is clogged.