So I finally (after two weeks) hooked up my car to get my CEL checked out...engine code P1153 came up...(Thats what AAMCO told me) they said they didnt want to fix my car because it had too many aftermarket parts...anyone any input on what the code is

 

I believe thats the front 02 sensor. It could just be dirty or needs to be replace. Remove it and inspect it.

 

disconnect it from the DP? clean it up a lil bit and put it back?

Car runs chill...should this be something i should worry about (like will it kill my engine)
Ive been getting bad mpg..im pretty sure its cause of this..

 

O2 sensor circuit range/performance (high) (Bank1 sensor1)


You can pin it out to be sure but it probably needs to be replaced. Might want to check with Ed too since he tuned your car to see what he says.

 

front 02 is the fuel control and rear is cat efficiency on all the cars ive worked on so bad mpg is pretty likely due to the sensor. you really cant clean out an o2 sensor.