Ok So I have a 2000 ex 300 that the coolant hose was leaking under the intake manifold so I replaced it and after reassembling everything I am receiving the PO 171 CEL code. I have checked all of my hoses & connections cleaned the MAF sensor with the MAF sensor and I was not having any CEL lights prior to removing the air intake, plenium & intake. In the past year all of the O2 sensors & A/F sensors have been replaced as well. What am I missing? let me know thanks

 

Did you use new gaskets? The throttle body gasket is square and it will line-up in any orientation but it will be right in only one orientation. Any other it will leak and throw P0171. Now how would I know that?

 

I did use new gaskets and I do believe that I lined up the throttle body gasket properly as well thanks

 

Well something is leaking. Good-luck.