147 2004 (jtd)
I've bought a 2004 Alfa Romeo 147 1.9 JTD approximately 1 year and a half ago with 120.000 Km. I've had a couple of issues in the past, but nothing too severe, alas there is one that bothers me pretty much every time I go into a highway.
Between 3750 and 4000 RPM, in 5th gear (130-140 Km/h), the engine turns on the MCSF (Motor Control System Failure) randomly. Sometimes it stays on, sometimes it turns off instantly.
There is a slight loss of power associated with it and I'm unable to properly accelerate at that point (if it's a steep climb, I might even lose speed).
if I drop below 130 Km/h (which is at 3750 RPM) and go back up, the MCSF light shuts off and everything is normal again. Cruising between 130 and 140 KM/h causes the light to turn off at seemingly random times.
The fun part is that if I somehow manage to go past 140 Km/h (4000 RPM) without the light turning on, it cruises along nicely without any kind of issue (the light doesn't come on any more, no loss of power).
Something is happening with the car during that RPM interval. I've taken it to the Alfa Romeo dealership and after me spending over 3k euros fixing random crap (cleaned all the sensors including MAF, cleaned the engine, replaced the EGR, the overboost valve, changed all the filters, etc.) the problem is still unsolved and they are unable to find out what's happening.
I don't have a code reader myself and I'm kinda inept at that to be honest, but the dealership told me the code read something about some kind of air flow leakage (which they are unable to pinpoint/solve).
Is anyone able to help me?