Cubfan

Wow, must be a problem. I had both mirrors replaced under warranty at 25K miles. The dealer charge was $1,395.74! I sure hope this problem doesn't come back at 50K.

I can't seem to find any owner's manual information regarding replacing the GS350 awd engin air filter. Where is it located and is it an easy do-it-yourself maintenance task?

Which dealership? Norwood mass why Norwood is Herb Chambers and it is actually in Sharon now. The service manager, Mark, is a good guy. Roni is my service advisor. I suggest you go for a ride or listen to another 2008 car and see if it makes the sound too. Also sit in a 2009 model and see if the sound is prevelent there as well. My only concern is you say you hear the tapping coming from the engine area and narrowed it down to the fuel pump. The fuel pump is actually in the tank which is under the back seat. If the tapping is coming from the engine area it may be the fuel injectors which several other members have noted/complained about. If it is the fuel injectors, the tapping will increase in frequency when the rpms are increased. steviej Hi ,the tapping is coming from the engine and its coming from a pump that is located on the left side of engine in the back area it was listened to and agreed that it was making a tapping nocking sound that 2 other cars of the same didnt do ,so they agreed to replace it , but still makes the same sound .Their's Def a problem and you can hear it when you aproach the car as well as sitting in it . I have a 2007 GS350 with a loud tapping sound at some start-ups and a softer constant engine tapping sound. I was told that the start-up tapping is the fuel injectors and the softer engine tapping is normal engine sound, and not to worry as both are normal sounds for that engine. Cubfan