2001 Cav 2.2 engine shaking issue

Thank you for reading my post.

2001 Cav, 2.2 engine (Base model). 150K miles. Owned the car for 10 K miles. no problems up until now.

Starts fine but runs rough vibrates.

Computer code indicated injector issue on #1 cylinder. So I replaced injector and the spark plugs as well.
Plug for #1 was completely fouled. The others were okay, but a bit old.
No other codes were found.
I didn't check the plug wires or ignition coils. My thinking is a coil sending power to one cylinder should be sending to both. Then again, I could be mistaken.
I did not reset the computer as I don't know how to do that.

My plan for now is to check the plug wires. If they're still good, then I'll look at the packs. Any other suggestions are welcome and appreciated.

Thanks,
MJ