I have a 2006 XB can't keep the thing running idles ruff and misses while while driving was told by one scion dealer it was bad gas, paid that bill now after 3 gas tanks of new fuel I took it to another scion dealer now I am being told it is a ecu has any one else experience this the xb has 78000 miles on it and I boughtit new and this is the only problem I have had with it.

 

have you installed a intake? whens the last time you changed/cleaned your air filter?

 

Could be in need of a tune-up, perhaps cleaning of the MAF sensor, or like Zach said, the intake could be dirty or the filter could be causing it...

I would suggest posting this thread in the xB forum, if you get no answers there, perhaps check out the Scikotics website, there are a good deal of xB owners that may have the information you need to get yourself squared away.

 

Make sure you don't have a vacuum hose off somewhere. You will here a sucking noise, and if's bad enough, the car will run bad, and or stall.

 

My 240 had a loose MAF sensor that caused this. Does it idle normal, dip down until the car shudders, and then rev up again?

I would definitely go over your whole intake system with a fine tooth comb and make sure everything is spotless.

 

thanks guys I am checking the map sensor tomorrow the shop told me that scion said they would help me to fiqure it out I will keep you up dated on the progress