What could this be?

LAlright, the other night I was doing some 0-60 runs while it was raining outside. Note that my car is pretty much stock 170k miles, new engine and tranny though. So roughly 240rwhp. Nothing crazy. On one of them, the tires were spinning as usual from a dig but the entire car started to shake violently. It felt almost as if it has massive wheel hop like a front wheel drive car, but I know that couldn't be.

After that, the service engine soon light came on for 5 minutes, then off again. That light for the past week went on for 1 minute and then off every 2 days. Take note that my engine and tranny have 750 miles on it. Just put it in 2-3 weeks ago.

Now when I'm driving, the car seems pretty normal. The only time I feel something is when I'm going 1mph in forward or reverse. The car lunges back and forth violently and I have no idea why. I did basic fluid checks and stuff but I don't know where to start otherwise. The engine sounds mint though, no noise from there.

The only other thing is when I was pulling out of the driveway last night to drive it and check things out, there was a popping noise coming from the front when I turned the wheel. It happened only three times and after pulling out, nothing. My steering fluid was low so I just put some in. No idea if that fixed it yet.

So the question is, where do I begin? I'll try to get a video of the car today if it helps.

UPDATE: There is a loud kind of clanking sound coming from the catalytic converter. I'm probably going to have it removed and just put a pipe there. I suspected it was clogged a long time ago.

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