Hello there everybody, I hope you can help with this problem.

Ford Focus MK2 1.8 TDCi 2005

Here goes, I've checked injectors with a leak back test and they all seem great! It goes into Limp Mode with the Cog light exclamation mark in the middle whilst driving majority of the time.. then what I've noticed is sometimes the cog light will come on and it won't put it in limp mode? And then occasionally out of nowhere it will be running and idling okay.. if it runs lumpy with irratic idling without the red cog on I'll switch it off and on and then the red cog will come back and it will be running better.. there's no EML lights just the red cog. Anyhow I've posted a Link of a video. It doesn't smoke when booting either. The EGR is running fine also.

 

 

 

 

have you put a decent fault code reader on the diagnostic port and read the fault codes? if not, you should

Well mine only reads DTCs I had the AA out and he didn't even know what the powertrain light was coming up for.. maybe I'll have too call them again 😒

5 hours ago, Naynay1991x said:

It goes into Limp Mode with the Cog light exclamation mark in the middle whilst driving majority of the time..

If the Engine System light is on, there will be a DTC for it. But some codes do not show up on generic OBD2 readers. It needs a Ford specific system like Forscan to read them. I have found just this with code P0299 on my car.

From the sound of that idle, I am suspecting a fuel pump or pressure problem. The leak off test seems to show the injectors are ok. Forscan can show the fuel rail pressure and the IMV duty, which is what controls the pressure, in real time.

I would not have thought that MAP or MAF problems would cause that hunting at idle. It is basically all about getting a small but well controlled fuel injection, and fuel rail pressure is critical for this. EGR flapping about wildly might do it, but I doubt it, and you say the EGR is fine.

I have real time data for my 1.8 from Forscan for comparison if needed. The pic below starts at idle, all flat. Accelerator (APP), Fuel Rail Pressure, RPM, Air Temp, MAP, MAF, Fuel Rail Temp.

Thank you for this I'll try forscan as soon as I can!

1 hour ago, Naynay1991x said:

I'll try forscan as soon as I can!

Bit more on the system here:

 

James (jeebowhite) has done a nice guide:
https://www.fordownersclub.com/applications/core/interface/file/attachment.php?id=58645