Hey people, just recently purchased a Lexus GS 400 for the steal and I am trying to figure out what is wrong with it. It stalls when turning all the way, when I come to a stop when driving, and it is running rich. Please help!

 

There is a idle control valve on the power steering pump. It uses a vacuum circuit to vary the amount of assistance the steering wheel receives depending on how fast your going. Sometimes the seals go bad and instead of allowing air to circulate its starts fighting the motor, so at extreme lock the pump can be difficult to spin, which can put some drag on the engine thru the serpentine belt. There are some possible other symptoms but if u just bought it, it’s a fairly easy thing to inspect and make sure it’s working correctly. And give u a chance to see if the power steering pump is leaking, most are. They end up leaking right into the alternator and can ruin that. So it’s a good thing to take a look at.
If your looking at the motor from the front the power steering pump is on the left side, halfway down and the alternator is on the bottom left. You’ll find two 1/4 vacuum lines running down to the valve. If u unhook them from the valve and check to so if they ends are dry or covered in atf? And we can go from there. Also see how everything down there looks, if it’s covered in fluid or all clean and dry? If it’s all wet, you’ll want to pull them out, and clean em up, and either rebuild or replace them.

 

I’ll make sure to check it out and get back with you. Thank you very much for your advice!