4runner has no power on acceleration can get it up to 55 but takes a while and will no pull 5th and barely does 4th, other day it ran good when it was cold had plenty of power but once it got warm it lost all power... idles smooth and starts right up have timing set checked AFM its good... brand new plugs wires cap and rotor... checked the cat its not plugged or anything... thinking possible the 02 sensor.. could it be bad and not throw a code?

 

How about a compression/ leak down test.

 

compression is all good checked that

 

Check for codes even if the CEL isn't illuminated.

 

I did check for codes still nothing. and I know the light does work it comes on before startup.

i'm just thinkning its got to be a connection to some sensor or something cause that one day after it started running bad it had good power then when it got warm it just immediately had no power again. I tried to do it again the next morning with the engine cold but hasn't happened again since that one day.

I've also checked all the vaccum lines and used starter fluid to see if there are any leaks and havn't found any.

 

might want to check the the egr stuff if one of the lines are plugged it could cause problems. also check your cat. pull it off and look threw it. have u had the smell of rotten eggs? could be a bad cat.

 

checked the cat already

 

He stated he had checked it in original post ^

But its not overheating or mixing fluids?
is it bogging or anything?

 

nope not mixing fluid or any of that stuff

what do you mean by bogging. it does idles prety smooth but i think it could be smoother.

It just doesn't seem to wind up fast enought and has no power like i'm dragging an anchor behind me down the highway except for that one day it cleared up when cold but just all of a sudden cut out like it was going to die then had no power when it got warm

 

put a new o2 sensor in it and it did the same thing ran good cold but then had no power warm.... then the CEL came on says code 25 running lean...

 

Finall got it fixed. it was a bad injector. the injector would work sometime then it would quit working.... put a new one in and all new seals and runs like it should finally...