Bad fuel additive...
 

1993 Camry LE

I put some fuel additive in the gas tank to boost octane. It was some cheaper stuff I bought at Wal mart..

Now, it runs rough! Is there anything I can add to this tank of gas to counter the bad stuff I put in it? maybe use marvel oil?

How much additive did you use and what was it?

Suggest you run a few tank fulls of gas through the engine first. Don't compound one problem (the additive) with another (Marvel oil). The problem might just go away as the tank is flushed out.

it was an 8 oz. bottle, makes the car run rough. I'll let it use this tank then not add anything to the tank for a while..

lesson learned...

The 4 cylinder should be able to run on low octane fuel. The injectors rarely need cleaning although dealers often try to sell this to customers.