hey, i have an 07 is250awd with 68,xxx miles. only other significant thing i can think of are megans ez street coilovers.

so when i turn on my engine, i can here a strange grinding noise... except it isnt really grinding o.o
sounds like something is loose. I thought it may be one of my belts, but they all seem fine. a friend of mine said he thinks it might be a loose pulley. does anyone know whats going on or have/had the same problem?

 

Sounds like the infamous "cam rattle". Basically it is a poorly design cam gear that loses its oil during a stint of sitting, especially in the heat. So when you start it up, its internal components "grind" slightly. I experience this, but only 5-6 times a year...mostly during the summer months after sitting for 9 hrs outside at work. What helps is a fresh oil change and FULL SYN oil.

 

Sound clip would help....

 

check pulleys, one of your just being bad. if you could record a video of it and post up here, so we could help you out.

 

bet you its the water pump.

 

had the same problem, it ended up being a water pump that needed to be replaced

 

Not sure if it's the same problem I had but the noise sounded similar, I thought it was the belt too but it ended up being the water pump. It was also leaking a redish fluid from under the engine which was also from the pump. Took it to the dealer and they replaced it under warranty

 

This is the same thing that happened to me and it turned out to be the water pump for me as well. 100% covered by dealer

 

I noticed the grinding noise with increasing frequency and really thought it was the starter drive failing. I bought the car three years ago this month and purchased a 3 year extended warranty when I did. I ran home Wednesday to check the date that it expired and was delighted to find out that it wasn't until July 14th. I called Lexus yesterday and they said drop it off and they would look at it today. The service adviser called before lunch and said that it wasn't the starter, but was in fact the cam gear issue. They called the warranty company to file the claim but to my surprise, the warranty company said they were going to send an adjuster out Monday to "verify" the diagnosis. Already feels like they are going to try to wiggle out of it. I'm sure they are pissed to get a claim that will easily cost them a couple grand, with only two days left in the contract. We will find out Monday. Made it clear to the service adviser that the car has been properly maintained and that this is a common issue. He assured me he would make it very clear to them when they came.