By cheap I mean you can probably get two for under $10...
When mine went out, I was on the highway, and it felt like I was hitting the brakes, off and on. Then it slowly got worse, felt like I was laying on the brakes, and if I gave it more gas, it would actually start bucking. If I stopped for a bit, especially if I turned it off, I could then drive for 5 minutes or so before it would start happening. It can cause some crazy stuff to happen. So, we agree, probably not it, but it is one thing that could cause this...
Since it's an RE, can't you just see what codes it's throwing? Or are you getting any warning lights when it happens? I don't know enough about fuel injection. Hopefully somebody here can help more.