I have a RX 350, 2007. When it is cold out and when I first start the car this tapping noice comes from the engine. I was told it was piston knock. Does anyone know how to get rid of this noice?

ccminar

 

What kind of gas are you using? I thought I had it on my last car and I was told yo use premium. Fixed the problem. Your RX is suggested to use Premium as well.

 

The tapping noise stops once the engine is warmed up. The dealer told me it is piston knock. Only does it when it is cold.

C

 

I have a 2008 rx 350 with 37,000 miles. I have the same noise. Took to dealer they said the same thing. I use premium gas.

 

What oil are you using in it?

 

It's piston knock or piston slap and there's no way to get rid of it. The pistons are just a hair too small for the cylinder. It really isn't anything that will cause a problem, it's just a pain to listen to. I have it in my RX, better gas will help but you just need the motor to warm up to expand the piston.