I am looking for some advice about where to turn with regards to my 2003 E300. For a while I have experienced intermittent hesitation and I just put up with it as it was only a bit annoying. It has since worsened to a lot of hesitation and lurching, to the point where, at times, I’m concerned about stalling out and/or getting rear-ended. I took it to my dealer. They installed and ECU update. However, that did not solve the problem. The service manager said that it is an “inherent condition” and it is operating as designed. When I asked him if Lexus designed all their cars to lurch, he said no. 
[I should remember to keep my sarcasm in check…] My service adviser maintains that there are no fixes available. I am still pushing there, but I am not optimistic. I saw a lot of ranting on the Club Lexus Forum. I’m not too sure if they are a rational source of information though. No real answers there anyway. They did talk of transmission software update [TSB #TC004-04R]. I’m checking to see if that is what I got. So, net is I am seeking advice on where to go, what to do, next. Or, is there really no option available?
Clean the MAF sensor. I take it there are no codes. Also, could be a cam sensor or fuel pressure.