madlion

ohk i bought my 00 civic si used with some aftermarket parts already built in to it.. so dont ream me for the chipped ecu its not a choice of mine damnit. my ecu throws a p0133 code which is delay of the rear oxygen sensor.. my mechanic told me the whip is running rich especially around 3-4 rpm.. here is what i think. i think the chipped ecu is meant for other mods besides what i have. i have a intake and an exhaust. so i think the engine is not getting enought air while its sending all that fuel.. the reason i think this. i put on a really nice airfilter. its not a cheap one it has a cone in it that swirls the air and looks real high quality. after doing this my car went threw a cycle after a day of hard driving the engine light went off. i didnt reset it. now it is my belief that it is because i switched to this nicer airfilter. i bought a vafc to correct the chip in the ecu. but the engine light went off. its still going to be installed and tuned. but should i wait to have it installed and tuned.. would any other mods make the car a lot faster if i tuned it.. like intake manifold. i dont want to get headers due to the turbo in the future. total cost of vafc2 install is 250.. 150 for installation and 100 for dyno tune.. i dont know how to do the dyno myself im going to get the man to show me because they let you dyno your own car for cheap and make adjustments at the place im going to.. anyways does this sound like whats happening? car previously had a turbo on it also. car idles at 1500 till it warms up then idles at 600-1000. also when im warming the car up its at 1500 rpm.. i turn the steering wheel and the meter drops to 1000 or 800 and gradually goes back up to 1500 until it is warmed up then drops down below 1000.. is that normal? 49k miles on the car b16a2 00 civic.
thanks peoples
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