ford escort 97 - service engine soon message

Hi,
I have ford escort 97, with quite low mileage: less than 100,000 km.
It now displays a message: "Service Engine soon". I took it to a mechanic
and he said everything is OK and it displays the message probably because something happened to the gas cap with time or something like that, I bought a new gas cap and the message did disappear for some time but then appeared again, the mechanic advised to take it to the Ford dealership no, because there are no obvious problems and he's not sure why it displays the message.. My question is does anybody know what could be the problem, the car is well driveable?
Thank you
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Vadim wrote:

It could be many things. Oxygen sensor, catalytic converter, gas cap, many others.
I would take it to Autozone or someplace and get the exact codes (all of them) read. Write down the codes, and report back to us.
Until we know the exact codes, we won't know what the problem is or be able to help you.
Jeff
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Part of the problem appears to be the mechanic.... His advice was bad and it doesn't sound like he has adequate equipment....
As another has mentioned, some auto parts stores will read the codes for free... avoid purchasing any parts until you've had someone without a "vested interest" advise you on which direction will be the least painful...
HTH
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Or interest in his craft.

write down the codes,,, not what they interpret them as.
--
Yeh, I'm a Krusty old Geezer, putting up with my 'smartass' is the price
you pay..DEAL with it!
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.