I've noticed this SEVERAL times. I have a campaign generating leads at $14 each ($3-4 CPC) and if I change the Geography or Pause the campaign, when I return it to the way it was, it falters and the cost per lead goes to $40. What I *think* is happening is they are dropping the position, meaning it's clicked by less serious buyers who are "shopping" and clicking lots of ads (that's how they made it to the bottom of the ads or page 2, etc.) Last week I was getting 10 leads a day consistently. I changed Geography from USA to a single state. NOTHING else changed. Now I changed back to entire USA for three days, and in three days, I've only had 4 leads (vs. the 30 I would have had if I didn't change anything.) Any ideas?
For the last couple days, Adwords has been messed up pretty badly. One day I see a keyword filled with 3 pages of advertisers, the next day, not a single advertiser remains. All of my campaigns are going under review randomly, and then back up in an hour. Everything is really messed up badly.
I actually had a nice AdWords campaign going directing visitors to eBay and was pulling some nice $$$. When eBay changed their policy and pulled out of CJ to do their own ad network, I paused the campaign. I have since created a landing page and restarted the exact same campaign, however the CTR is horrible and I don't believe it will ever get to where it once was. I believe if you raise your spending limits until the ad starts getting good CTR again it may work.