I drive a 2006 hyundai elantra with around 30,000 miles on it and lately there has been a rattling noise coming from the engine bay. It happens around 2000 rpm and only in drive. I narrowed the noise down to the area around the waterpump and alternator. I also tried turning the AC on and off and I found that the noise was greater when the AC was turned on then when it was turned off. What could this be and how can I fix it?
Check A/C idler bearing for noise, take off belt and feel for rough operation or noise when you free spin it.
January, 18, 2011 AT 5:35 PM
Checked that and it ran smooth without noise. I also went around and tightened every bolt I could reach. There is another problem, I dont know if its related but, now im getting a check engine code 2270 saying that sensor two is lean. This code pops up and goes away at seemingly random intervals. The noise also has developed into a sporadic sound. Sometimes it is there and other times its not. I took the car to a mechanic and replaced my A/C compressor but the noise and light still remain. What else could it be?