P0174 : system too lean (bank 2)
P0300: random misfire detected
P0302: misfire cylinder 2
P0304: misfire cylinder 4
P0306: misfire cylinder 6
p1153: a/f sensor circuit response malfunction (bank 2)

Ok so here is the symptoms I have noticed. When driving the check engine code will flash then go back to solid and the motor will stutter then drive normal. I replaced the maf already with a new one but havrnt changed the air filter and its pretty dirty. From what ive read it could be a bad o2 sensor or a crack in the exhaust or a bad gas cap. I just would like any help I could get on the situation.

On a side note I pulled the whole top of this motor apart a year ago and got them resurface with all new internals due to a bad exhaust valve in cylinder 2 so I'm hoping I don't have to go through that process again.

 

Welcome to Club Lexus.

Please go through the sticky, specially having problems start here mega thread.

Form a strategy based on the first code after clearing the codes.

Make sure your battery is fully charged and then go after misfires and then work your way to the emission codes.

2/4/6 together can be due to OCV [DIY in sticky threads will walk you through the process.]

Salim

 

I already bought a new o2 sensor for that bank (haven't installed it yet) and after I replaced the MAF I rest the codes and that's when the car started acting like it is with the check engine light flashing and all the misfire codes. Could it be from the MAF sensor or is it more likely the 02 sensor malfuntioning.

 

Sart by fixing ignition and not emission. If you are misfiring on bank 2 .. 2/4/6 then O2 sensor will detect unconsumed (free) Oxygen. There maybe nothing wrong the the O2 sensor and MAF.

Salim