Hey all. I have a 99 expedition 5.4 w/120k. It is my first ford and I love it. However I am having a few issues. I keep getting a bank one too lean code. I've tried tracing the vac lines, to no avail. I am hearing a loud whoosh though when I shut the truck off. As the truck cools down the whoosh sound diminishes accordingly. Like I said this is my first ford. Is this a normal occourence with all ford's?


Also Any info/diy power steering pump replacement for the same ford would be appreciated.

Thanks for all your help

 

This is a bit old, sorry nobody replied. The intake noise you hear after turning it off is somewhat normal. Although a lean code does normaly point toward a vacuum leak. You might have missed which lines to look for. Check your pcv lines from the passenger side pcv valve, follow then around to the back of the throttle body, there is an elbow back there that was notorious for dry cracking, causing a leak. Make sure none of the lines are collapsed or cracked. Also make sure your pcv valve is functioning. You should be able to shake it and here it move.