Introduction and motor control system failure
I've just bought a 156 jtd 16v SW. Really nice car...It has all the looks, leather interior etc. etc. etc. EXCEPT.... for the motor control system failures I'm sometimes getting AND some strange noise I sometimes hear.
First about the Motormanagement errors: I get this every few times I drive, most of the times after 5 minutes driving, but can also be half an hour. Sometimes 3 days no problems. Occurs most of the times when speeding up a little bit, or when gas peddle is at 100%, to accelerate (or when cruise control resumes again).
What has been done:
went to Alfa dealer and hooked it up to the examiner. Turbo pressure sensor gave incorrect value according to the guy. So he replaced the sensor (was very dirty because of exhaust gasses/egr..). Problem occured again. so made a new appointment.
Again examiner showed up the turbo pressure sensor that gave a faulty value. Because I also hear sometimes some mechanical noise when my rpm is around 2800 rpm and because the turbo pressure sensor was really dirty I asked the guy to clean the EGR. I'm not sure if they cleaned it very througohly, but they told that the valve was indeed dirty (of course...). I'm also very shamed when I accelerate from 80 to 120 km/h, especially when it's dark I can see the black dirt in the headlights of the cars that are behind me... So I thought this was EGR related...
tomorrow new appointment with the dealer to replace some other sensor (think the overboost sensor?, located near the radiator at the front of the car). I will also ask them to double check all hoses related to the turbo and air intake, and the air intake itselves.
When accelerating in second gear, I *sometimes* hear some mechanical grinding like sound. I started to hear it just before shifting up to the third gear when I'm off the throttle. Dealer guy says it's some air resonation because I pointed out it was during the time when I suddenly get of the gas throttle...However I also hear it sometimes when just accelerating in the 2nd gear. I've tried to make a sound recording, but had no success yet to have a clear recording. Problem is, it's not always the same and some other times much louder. I had also a few cases (2-4) where all power was gone. All of these times this was NOT related to any engine error popping up on the display.
Maybe if you have any ideas I can pass it on the the alfa guy looking at my car.
btw: EGR is one of the last models: electrical valve. Earlier models can be capped with a blank plate when they give problems, with this engine (156 jtd 16V) of a later (third/fourth??) generation, it can only be done by software if I'm correct, and then not for 100% close the valve. Not sure if these problems (strange sound and the motor management errors) I'm having are related to eachother...
Last edited by bellamacchina; 30-09-08 at 14:28.