I just came back form a vacation. Drove my 2006 HyHi from Houston to Miami and back for the second time this year (last time in August without any problems). 200 miles from the start, CEL came on. Went to the local Autozone and got P0300, 301, 302 and 306 readings. I had the same readings in 01/2010 (got cleared by Toyota) 11/2010 (changed spark plugs and cleared by Toyota) and now again in 12/2011. What is going on? The same issue every year around the same time (winter? colder temperatures?) I took to a local mechanic along the hwy 10 (luckily we worked at Toyota for 30 years). He did some scans and told me that everything is OK, suggested to use Fuel Injector cleaner for a few cycles. So I did until I got to Miami. Just FYI, I NEVER noticed any performance problems and/or noises coming from the engine. So I got to Miami, cleared the CEL and drove around fine until I got back on highway heading home. As soon I accelerated to 80 mph, the CEL went on and stayed on. Then every time I went to 80mph, it would start flashing and then went steady when I slow down. Any ideas, PLEASE? Thanks.