1995 Town Car Variable Steering Problems

Hi Bill,
I have a 95 Town Car Cartier with 141,000 miles on it, the electronic variable rate steering seems to be giving me an issue. I have the switch on the dash set to high, for the firmer feel, but I can drive the car for about ten minutes, and then the steering gets real easy (feels like my old Mark IV). If I stop and shut the car off, when I restart the steering is firm again for a little while then gets real easy, I tried moving the switch on the dash, once it gets easy, to low med and back to high and nothing changes. Just as a note, my air suspension is working properly. I would appreciate any help on this. Thank You.
Scott
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Hello Scott –
The condition that you describe must really make driving unpleasant for you at times. I know it would for me.
The E.V.O.or Electronic Variable Oriface steering varies the size of an oriface at the power steering pump in order to provide a variable steering effort for the driver. It does this electrically using multiple sensors that include a vehicle speed sensor and a steering wheel speed sensor and an adjustment switch for the amount of effort desired by the driver. The reason that I am explaining this is because it all leads to an electronic control module that receives the combined information from the sensors and switches and then applies the correct voltage to control the Oriface actuator. The module on (most) Lincolns of that era is also tied in with the Suspension module. Anyone working on this system must read the appropriate manual for their year of vehicle to understand the theory and sequence of operation.
The good news is that a diagnostic connector is provided for a technician to gain access to diagnostic codes from his proper code reader. Obviously this is not a Saturday morning “quick fix” before coffee time repair for everybody. If you want to trouble shoot this yourself you are limited but there are a few things that you can consider. Did the problem start immediately after another repair such as air suspension, power steering pump, anything in or near the steering wheel or shaft etc. etc.? This information is valuable to any technician that will be working on your car. If there was any work done near or at any sensors, switch etc. for the EVO the electrical connectors could be re-examined for a bad connection. If you are going to attempt the repair yourself, I strongly advise that you have the appropriate manuals at your side. If you will be taking it to a shop for the diagnosis and repair be sure to choose a qualified shop otherwise the possibility of too much guess work and incorrect parts replacement exists. Feel free to contact us for any further information or for any parts or manuals that we may be able to provide for you.
Wish you the best of Luck,
Bill