Noise problems are almost impossible to diagnose without physically listening to and locating the source and understanding the type of noise.
From what you have described, it could be anything from valve clearance noise, piston conrod or crank pulley.
If the noise only occurs with abrupt acceleration, it most probably is from the con rod bearings. If the noise occurs with slow and constant revving up of the engine, it could be the valve clearances requires adjustment.
But if the main noise is with the whistling and chirps, the most likely cause would be the beltings and crank pulley.
Autozone provides free scanning services for the CEL, get it done and let me know the exact trouble code. If it is related to the exhaust conversion, it most probably is a fault with the catalytic converter or HO2S sensor.
Saturday, December 5th, 2009 AT 12:36 PM