Vehicle has 59k miles. Dealer wanted to replace the throtle module. I did a code check myself (p1171). Cancelled the check engine light several times, but error always reappeared within a few miles. Surging problem was fairly dramatic, almost stalling the engine out. Today, I replaced the MAF meter with new one ($205 from dealer, five minutes to install myself), and most of the problem has disappeared. Still fluctuates plus or minus 50-75 rpm, but check engine light, so far, has not returned. I'll consider cleaning the throttle module next, but car runs great now.