...the sound is like the sound a bad muffler might make...also sort of a rattling/vibrating type sound...but sound comes from in front under engine...sound occurs only when i hit the gas pedal...sound goes away when i hit desired "cruise control" speed...engine light has not yet come on...any thoughts? thanks

 

Have you checked the flex pipe?

 

Have your exhaust checked out near the flex coupling and around the bottom of the WU-CAT. [area around the oil filter]

Salim

 

I'm not sure what a bad muffler sounds like but if it sounds like a metallic chattering noise, I think I have the same thing. I've been told that it is related to some sort of heat shield and the bolts come loose and the piece will rattle. Haven't looked into it further than that though.

 

knocking/pinging?

 

I hope it is not transmission, which is located under the engine and it will be whining when you step on gas.

 

flex pipe it is ... all good...no charge from the toyota service place i have gone to for years...(prius/rav4)...thanks for the input...

 

First diagnosed here remotely by hyper and with no charge.

I would suggest stay here (CL) and post often, specially to help out others.


Salim

 

Haha, Club Lexus is pretty awesome!

Glad to hear you got it resolved!

 

I do not mean to high jack this thread but I have had a loud clicking noise coming from the front end on the passenger side when getting up to speed and then will go away when at cruising speed. Could this be what you were hearing? it felt like a front end gear issue.

 

CV joint? Is it worse when turning?

 

I was wondering that myself but the only time I hear it is when I am accelerating to highway speeds from either a slow start or dead stop. Once I level off the clicking goes away.