...when tested the code readout was the egr low flow.
I assume that you received code P0401. If you did, then basically your EGR (exhaust gas recirculation) system seems to be having problems. This seems to be common on Contours.
According to the Ford service CD, this can be caused by the following:
-- EGR valve stuck closed or iced.
-- EGR valve diaphragm leaks.
-- EGR valve or flow path restricted.
-- EGR vacuum hose off, plugged or leaks.
-- VPWR circuit open to EGR Vacuum Regulator (EGR V.R.) solenoid.
-- EVR circuit to PCM open.
-- EVR circuit to PCM shorted to PWR.
-- Differential Pressure Feedback EGR (D.P.F. EGR) sensor pressure hoses both off.
-- D.P.F. EGR sensor pressure hoses reversed.
-- D.P.F. EGR sensor VREF circuit open.
-- Downstream pressure hose off.
-- Downstream pressure hose plugged.
-- Damaged orifice tube assembly.
-- Damaged EGR V.R. solenoid.
-- Damaged D.P.F. EGR sensor.
-- Damaged PCM.
Check the EGR and connecting tubes first. Check the tubes for blockage and vacuum leaks.
Cleared the light, ok for 2 days and then on again.
The reason that the light stays off for 2 days is because of the way a CEL (check engine light) is stored. A CEL is stored as follows:
For the fuel system a CEL is stored if a malfunction results during 2 out of 3 consecutive "drive cycles". A "driving cycle" is engine startup and shut down.
In other words, once you reset the code it will only be set again if the problem happens during 2 out of 3 "drive cycles".