Hello and good day all. I recently purchased an 03 expedition and have had some power steering issues over the last few weeks. It seems like the speed sensitive steering is all whacked out, sometimes power steering works flawless, sometimes the steering only works while driving , sometimes it does not work at all, sometimes while driving into a car wash it doesnt work and works on the way out, sometimes it works after I get gas. Now it is not working at all, it seems like if it were the PS pump it would work at higher rpm not at lower but I have seen the exact opposite at times. Maybe a completly seperate issue, I found a vacuum hose disconnected. the hose runs from the passenger side wheel hub, to driver side wheel hub then up near the break booster, then an open hose with no connection or other hose in sight (seems like a stretch but who knows with this advanceTrac system) Also no mention of any vacuum diagram, or advance trac in my Haynes manual.

 

Have seen where Body Control Module (GEM Module) caused similar problem.

 

Is there a way to check the GEM? This truck's systems seem to be a mystery. I cannot find information on the steering system how the evo functions, what sensors control the speed sensitive steering. Today I did a visual around the fuse box on the passenger side kick panel, nothing out of the ordinary. Today I took it to the store and blasted through a huge puddle, the steering worked perfect after being parked for 20 minutes but slowly deteriated to about 75% after a few more stops. Seems like an electrical issue I need to track down but my Haynes manual is severely deficient.

 

There is a way to check it, but it requires a scan tool.
If there is an Autozone around they will scan the computer free of charge. They cannot check the GEM module ,but if there are any codes in the computer they can tell what they are, and if there are any please have them give you the code numbers.
There is also a power steering pressure switch in the system, but I wouldn't condemn it without checking it first.

 

Hey Hanky, thank you for the reply. I put an obd2 scan tool to it and it didn't give me anything. I was ready to buy the power steering pump yesterday until the dang steering started working, i assume a pump fails or works and won't go back and forth.

 

When you say , didn't give me anything, do you mean no info or no codes?

 

The reader gave me the real time info, but no stored codes.