I have a 08 Focus TDCI which continually surges from 900 rpm to about 1400 rpm when stuck in traffic Mainly in 1st and 2nd gear.
Does anyone know what may cause this?
The garage say this is normal but have no answer, This is not normal or they would not sell as well as they do!!!
Any help would be appreciated, Thanks
On the TDCI the EGR valve or injectors are known to cause problems leading to surging. I have a 2004 C-MAC TDCI and had to replace the EGR valve, and have experience of failed injectors as well. Both problems cause surging in a small rev range at a particular throttle setting.
The one test they do on a diesel for MOT is to acellerate the engine quickly from idle to high speed (high speed defined by how brutal a tester you have). The idea is to get the engine quickly to 100% fuelling and to check for dense smoke of any colour. It is to check for any smoke that will obstruct the view of other drivers. Do this and check the smoke you get - if it is a dense black cloud you most likely have one or more injector that is probably not working properly. Try this three times and have someone at the back look for smoke.
What tests have Ford done? Did they just check the diagnostics port? The EGR and injector problems does not show up as error codes in my experience. They at least need to do a return test on the injectors to see if all the injectors are within specification. The injectors use the pressure of the diesel to open the injector and the rest gets injected to make noise, power and smoke. The part of the diesel that is used to open the injector returns to the tank through the tube at the top of the injector. The amount of the diesel returned by all the injectors must be very close to the same volume. If you have a faulty injector it will return more or less than the others.
If your car is still in warranty you need to insist that Ford test it properly and get it sorted before your warranty runs out. It could be expensive to fix and Ford will do their best not to pay for it under warranty.
If your car is out of warranty and you need to replace the EGR valve try Eurocarparts.com. It is the Valeo EGR Valve Part Number: 424590070 that is used on the 1600. It is cheaper than Ford by miles. I have no source for injectors (yet). I prefer out of principle not to buy from dealers if I have any option.
Eventually found a Ford Dealer who looked at the car under waranty without any questions, They re-loaded the ECU (I believe) and this is now I would say about 95% OK and Reasonable to live with.
I will look at the ECU valve though as this is not 100%.
Thanks for the help.