Hi folks. I've read through the excellent PS bible and I have a question. I clearly have some kind of power steering leak, as I periodically need to top up the power steering fluid reservoir. But I have no leak spots/puddles under the car where it is parked. According to the previous posts, it seems that this would suggest a failure of the ACV valve. However, I do not have the cloudy/smoky exhaust on startup that is symptomatic of the failed ACV.

How do I know which it is? Is it a leaking power steering pump, or is it a failed ACV? And how much should I expect to pay to replace each at a Lexus store?

Thanks in advance guys.

You may not see smoke. Pull the little hose at the front of the upper intake and check if it is oily.

I am having same issue.....and a high rev at start up, but no smoke. Let me know what you find out.

Lextek: Thank you very much for responding. I had a look under the hood and here's what I found.

1. I see two little hoses at the front of the upper intake. One very small hose that is not secured by a clamp, and another slightly larger one that is secured by a clamp. The larger one seems to run to the bottom of the power steering fluid reservoir. On the larger hose, I undid the clamp, but was unable to pull the hose off of the intake housing. I did not want to force it off for fear of breaking something.

2. While having a good look with a flashlight toward the bottom of the power steering fluid reservoir, I noticed that the hose connections and associated hardware at the bottom of the power steering fluid reservoir were quite obviously very oily, as if the there was a leak from the bottom of the reservoir.

Lextek, what do you think? I very much appreciate your lending your brain to this. Thanks in advance.

There is a small o ring at the bottom of the res. that usually leaks. You have 2 vacuum lines that run from the idle up valve to the top. One will terminate on the plastic tube of the intake horn and the other will go to the front of the upper intake. Check the one on the upper intake to see if it is wet inside. The hoses have probably become quite hard and it wont hurt to replace it. You will probably break it trying to get it off anyway.

The o ring is a simple replacement. Be sure to clean the screen inside very well when you have it off.

If you don't see anything under the car it's, more then likely, leaking into the alternator. Get the leak fixed ASAP and if it did go into the alternator you might need to change that in the near future.