Ford Focus Turnier 1.6 TDCi engine light on, diagnostic software says it’s the particulate filter or the exhaust gas recirculation valve
I bought a used Ford Focus Turnier 1.6 TDCi 2008 model. The first months it run fine, took it for the 140000 km service, it was all ok. One day, as I was getting on the highway, the engine light went on and the message on the screen was “Engine systems fault”. I was on my way to the airport that day, so I went on my trip and came back after a few days to the car. The same lights were on. I called the ADAC, which is like AAA here in Germany, and they came and hooked up the laptop to the computer, and it showed that the particulate filter had some kind of problem.
Long story short, I took the car to the garage, they initially changed the pressure sensor, in case it was giving a false signal, this did not resolve things, so they proceeded to tell me that I either needed to clean the particulate filter or change it. Since the car already had 160000 km and the filter had not been changed by the previous owner at the suggested 120000 km, I decided to change it, just to be sure.
After a couple of weeks or so, the engine light came on again, though this time there was no “Engine systems fault” light on. I took it to the same garage and they said it was the exhaust return valve and it had to be changed. I was kind of upset, since I had already paid a good amount of money for the previous work and it seemed that it had not solved the problem. So after having a heated discussion with the manager of the garage, I took my car to the Ford service station. They also said that the exhaust gas recirculation valve had to be changed, and so they did.
Again for about a month everything ran fine, until the engine light went on again. I took it back to the service station, where they told me that it is possible that the part they had placed was defective and they would have to remove it and place a new one. Fortunately, the money that you pay to them includes a warranty, which means I did not have to pay for the new part, nor for the work necessary to do the replacement.
A few weeks go by, and the light goes back on again. Went back to them, and they said that it is possible that the engine control unit is faulty and therefore giving the wrong signal, or somewhere on the wiring harness there was damage. Luckily I was going on vacation for a week at the time, so I left the car with them, to figure out which of the two it was. Coming back from vacation they told me the problem was solved with just an update of the car computer software. An update necessary, because the software had bug, which of course Ford did not say was a bug.
Now, I cannot be sure what happened. I don’t know, if it was the software bug, that gave wrong signals to the exhaust gas recirculation valve and this caused the particulate filter to get backed up. Or if the events where completely unrelated. But it seems to me, that anyone facing the same problem should first check if the software needs an update, and then proceed to check and maybe change the exhaust gas pressure sensor, the particulate filter, the exhaust gas recirculation valve, the engine control unit or the wiring harness. And it can save you a LOT of money.
I hope this is of help to someone.