So the guy at the shop that I trust said that when he was driving the VX and the valve clattering problem occurred he said the codes that were thrown were that the VX was running lean (I think he said 2 error codes up stream or something like that). This is an intermittent problem, that has been happening far more frequently here lately, and will eventually kill the engine after 45-60 mins of driving in a day, so what is most likely the problem?

O2 sensors or the MAF sensor?

Are O2 problems intermittent or consistent?

Where have you all purchased O2 sensors from?

Thanks. Oh yeah the problem is like this: drive more than 45mins or so = valve clatter, try to continue driving more than an hour = engine dying every 5-10 seconds, pull the MAF sensor plug and you can limp it home and the valve clatter goes away after pulling MAF plug but engine runs rough at times, but no clatter.