I got a vx-srs2, put extractors, exhaust, the thing is lagging had the engine light come on while on cruise control, also when i'm driving about 60ks i feel the car pulling me back just a little and sometimes make a popping sound went to an auto elec did the diagnostics, said it was the camshaft, sensor, so i changed it prior I changed leads and plugs. o2 sensor was fine.

Anyone got any idea's what it might be?