Intermittent fault
Q Since owning my 2007 Ford Focus 1.8TDCI there has been an intermittent fault which brings up code P0489 EGR flow low. When it happens there is a huge flat-spot and little response from throttle input until it clears after a few seconds and then drives normally.
The local Ford agent fitted a new EGR actuator to no avail, they then wanted to charge £1650 to fit a new inlet manifold, which I refused.
I have removed the inlet manifold and cleaned it thoroughly and the EGR valve moves smoothly – must have been a sadist who designed it.
There is a full Ford service history showing the fuel filter was changed 3000 miles ago. I recently renewed the coolant at which time I removed the EGR cooler and confirmed it was NOT blocked.
I have a Launch CRP Premium code reader and a multimeter. The most recent activation of P0489 showed freeze-frame data – Load value 0.0%, Coolant temp. 28°C, Intake MAP 103.0 KPA, RPM 1482, Speed 24kph, Fuel rail 44070 kpa
I’m beginning to think there is a wiring fault but have struggled to find a wiring diagram for the EGR actuator, and don’t know what normal readings to look for on my code reader.
Clive Willacy A Although the problem may be the EGR valve this would be an internal fault causing a circuit problem and the most likely reason for the P0489 code is a wiring short to earth in the loom. As you have had a new EGR valve fitted the possibility of it being a problem in the unit has been eliminated.
The first check would be to remove the ECU plugs and carefully check for any signs of corrosion or indication of a poor contact such as slight burning. If the plugs and terminals look good then I would use a continuity meter to check the wiring between the EGR valve and the ECU.
The terminals on the ECU which are relevant to the EGR valve are l2, d4, d2, d3. On the B plug is the centre of the three on the ECU and the pins are readoff from the top row left to right which is numbered A1 – B1 – C1, etc. The next row down being again from left to right on the plug side A2 – B2 – B3, etc. There is not a letter ‘I’ in the row so the row reads from left to right on the plug side – abcdefghjklm
Hopefully these tests will highlight any problem within the loom and should help solve the problem.