Experiencing something weird when I'm on the highway going to work in the morning. After being on the highway for a few miles and keeping a steady rate of speed, I feel the car hesitate for a split second. Thinking it was strange, I observed the dash and it happened again. This time I noticed that the CEL went off for that split second (it's been on due to a P0420 code that I haven't gotten to yet) and the RPMs dropped as well. It's almost as if the electrical system in the car "dies" for 200mS then is fine. I've only noticed this a few times.

Any ideas on what might be wrong or more importantly, what might fail and strand me on the highway? It's making me nervous.

 

Battery cables clean and tight ???

 

I am pretty sure - I replaced the battery within the past couple of years. I also did not see the battery icon light up on the dash when the drop occurs. You can actually feel the car jerk a little bit when it happens, almost as if I took my foot off the gas and pressed hard on it again.

 

I'd check the cables and be sure the battery itself is mounted and not shorting out against anything

 

That is exactly what I just had and it turns out that the battery harness came loose and was laying on the battery connections which is what caused it. Don't think the chances are good that you will have the same issue but its worth a shot to be sure.