Loud whining noise on startup! Air Pump? S320
I have a "loud" whining noise upon first startup of engine then it will stop after short drive time or minute or two. I believe it may be the electric air injection pump as it appears to be coming from it. It seems to be louder now that the weather is warmer.
Any thoughts on this symptom? Could the air injection pump be going out or a valve not working?
Thanks...
Air from the Air Pump was not going through the Secondary air pump or EGR thus the whining noise.
*CAREFUL when you work with or around the tan colored vacuum tubing, as it ages it gets VERY BRITTLE and will break at the slightest bend or pressure. The same tubing runs next to the spark plugs and coils under the engine top cover. If it does break on you, you can use small diameter rubber tubing to reconnect the broken ends together.



