I have a 2004 ES330 similar to a hestitation problem. It is good from a full stop but in imitation of I go not far off from turns on onto highway ramps, behind I pain the accellarator (sp?) it hesitates for 2 seconds past reving up. I ve taken it to a mechanic and he says it is normal. I have an 2003 Avalon when the similar engine and it jumps off the begin and has no hesitation. Mechanic s Assistant: Will the headlights turn on? Is the battery thoroughly charged? With or without headlights on. Relatively new battery. Mechanic s Assistant: What is the model of your 04 Lexus? ES330 Mechanic s Assistant: Are you fixing your vehicle yourself? What have you tried for that reason far? I ve cleaned the MAF sensor. Checked for contacts in the intake. subsequent to I put my Turbo OBDII app on, everything seems good except that the TPS stays constant concerning 30%. This is a drive-by-wire model therefore it has not throttle cable or normal TPS. I acknowledge the TPS is integrated with the throttle controller/motor. Mechanic s Assistant: all else you want the mechanic to know in the past I connect you? No, I guess that is it.
Its with worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a sick pump will all outcome in insufficient fuel instinctive delivered to the engine. Might in addition to be worth cleaning out the idle rapidity direct motor / valve as these acquire clogged stirring behind carbon and some brake cleaner washed through helps release things off.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you happening to date upon all maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms taking place and is warmed up? oftentimes in engine put-on many factors may cause the similar symptom(s)