Check engine light

Hello there. If the code is a P0420 or P0430, it's indicating that a catalytic converter isn't working as well as it's supposed to. The most proper fix for this is replacing the cat, which can get pretty pricey.

If money is a concern, there are some backyard tricks that you can do to milk a little more time out of it. The one I've personally used is to start the engine, pull the brake booster vacuum line off of the booster, and use it to suck down a can of seafoam ($7.00 at the local parts store). It will create a significant amount of smoke, so don't do it when the neighbors are around. Shut the engine off after the whole can has been used, and let it sit for about a half hour. Then take it for a ride, and drive it like you stole it. Believe it or not, I used this trick and it kept the code away for over a year.

Another trick that I've heard of is to take the converter off and soak it in a bucket of liquid tide laundry detergent. This is a longer term fix than the seafoam trick, and I can't say that I've ever tried it. But I've heard it works and have seen some YouTube videos on it. I'll include instructions on removing the cat in the images.

The last trick is to get an oxygen sensor non-fouler and install it between the downstream oxygen sensor (the one after the cat) and the exhaust pipe. This trucks the computer into thinking that the car is operating better than it actually is. It may be an illegal emissions modification wherever you are though. So be careful with that idea. You can find non-foulers on eBay and Amazon.

Hopefully one of these ideas will do the trick for you. Personally, I'd run seafoam and a non-fouler (they're legal here, for now). That would be the simplest and cheapest thing to do.