I have a 2005 RX330 and am wondering if the engine can be damaged by timing belt failure. I am reading conflicting statements on this site.
Thanks
ps. Also looking for an answer to my query regarding the entry point at the firewall for cabin air.

I don't remember a debate on whether or not an RX V6 engine is an interference engine. It is.

As I posted recently in the LS400/LS430 section, the cause of the broken timing belt on my first Lexus was not belt wear -- it was a seized water pump at only 75,000 miles. The few other broken Lexus timing belts I have personal (not forum) knowledge of were also not due to belt wear. All were caused by some mechanical failure not related to the belt itself. That's why it is important to replace ancillary parts (water pump, idler, tensioner, etc.) when replacing a timing belt.

What 1990 LS 400 said is true. The VVT-1 engines are interference engines. it is something that has been debated repeatedly on the Lexus forums. Because it is variable timing there may be times that you don't suffer damage because of a broken belt but don't ever count on that. Gates says the VVT-1's are interference, take it to the bank, rather than going to Las Vegas on this one. They are an extremely durable belt and extremely good parts (including bearings), but as 1990 said, belt breakage CAN happen because of other reasons.

A good friend of mine is a master Toyota tech ... he recommends changing the belt at approx 105-110K on the 3.3L V6. I know others have recommended a longer interval, but I took my friends advice because it was relatively inexpensive (~$450 for belt/water pump) -- compared to a belt breaking. As usual, YMMV.

Did your friend give you a deal on that? That is extremely reasonable.

He lives in another state, otherwise he probably would have ... :-) But, this was an advertised special at a shop that specializes in Toyota/Lexus. The actual coupon was $189 for a timing belt replacement, however, if you add the water pump (and who wouldn't), it added about $250. Add in the serpentine belt and there you have it. Oh, and yes, they only use OEM parts ... I can't believe the dealer wanted $1200 .... wow.

Thanks to all of you for your input. I think I now have a good grasp on the need for replacement of timing belt and water pump when the time comes. I will continue to watch this thread for additional information, if any.