Alfa Romeo Owners Club of Australia Forum

Technical => 932 Series (156, GTV, Spider, 147, GT, and 166) => Topic started by: alfamickp on April 15, 2012, 04:02:06 PM

Title: 156 V6 2003 auto "motor control system failure"
Post by: alfamickp on April 15, 2012, 04:02:06 PM
Hi hoping for some advice

Have a 2003 156 2.5 V6 auto update with the newer dash that tells you when things go wrong!!. 110,000ks  engine light has just started coming on at startup with "Motor Control System Failure" GO TO DEALER in the centre display flashing.
Crazy thing is car drives fine no probs with performance at all. engine light is on all the time now. Any way to reset?
Hoping for disconnect battery for an hour?  :)


cheers

Mick
Title: Re: 156 V6 2003 auto "motor control system failure"
Post by: Davidm1600 on April 15, 2012, 04:31:01 PM
Hi Mick, My '03 JTS 156 also last week decided to tell me the same thing.  And like yours mine seems to be driving ok, but until I can get it on the engine analyser I am doing my utmost to avoid driving it.  The reason why is that the message is an indicator that something perhaps is not right with our cars. There are (in the case of the JTS) 4 engine emission system sensors, and as anyone who has had a 156 for any length of time should be able to tell you they fail with age.  I have already replaced 2 sensors on my car in the past 4 + years over 30K kms of driving.  My car now has around 119,000km. 

So what I am simply trying to tell you is don't ignore it, get your car checked out. It might be something simple like your computer has misdiagnosed something and a simple reset is all that is required but equally it might be that a sensor will need replacing soon.  The alternative is to wait and hope you don't break down.  That happened to me the first time, and I had to have my car towed to my mechanics.  The cost for sensors seems to be different depending on which one.  The first one cost me around $200 to replace, while the second one around $400, I am hoping that if I need to replace my third one it won't be too expensive.
Title: Re: 156 V6 2003 auto "motor control system failure"
Post by: colcol on April 15, 2012, 04:32:38 PM
If you disconect the battery, i hope you have your security code for the radio, so it won't lock you out, disconecting the battery, worth a try, but you may have a Lambda sensor, cat, air flow meter or a million other things, they may be working out of its tolerance zone, if you have a code reader, its only going to tell you whats wrong, and you are going to have to replace the faulty part, if you go somewhere, make sure they have the Alfa Examiner, Colin.
Title: Re: 156 V6 2003 auto "motor control system failure"
Post by: wankski on April 15, 2012, 04:47:57 PM
if the engine light stays on, you have a persistent error which is stored in the ecu. you will need to connect to the ecu to clear it.

period.

disconnecting batt - waste of time. bosch isn't that dumb. something's wrong, attend to it.

don't drive it too much... could be over fueling or storing a misfire code... bad for the expensive pre-cats...

as the msg says 'go to dealer'....
Title: Re: 156 V6 2003 auto "motor control system failure"
Post by: alfamickp on April 15, 2012, 09:19:54 PM
thanks guys appreciate the advice.

Ive had more alfa's than I can count over the years I much prefer the ones without computers!!.
Give me side draft dellortos anyday!

Anyway I let the 156 sit for a few hours then started it and engine lights off!!
Im old and wise enough to know that they don't fix themselves so no doubt it will be back.

Its all part of the experience!

Cheers

Mick
Title: Re: 156 V6 2003 auto "motor control system failure"
Post by: wankski on April 15, 2012, 09:28:09 PM
in that case its a transient error... it may come back... what that means is that the codes are separated by a one off error or a persistent error ...

transient could be bad lambda signal (likely)

what can turn that into a permanent is if that leads to a misfire, then that will stay on.

if you plug it in, you will see all recorded error until you clear then.... only presistent will give an engine light that stays on.... doesn't mean you don't have an issue, but monitor it...

if you wanna DIY you can... google alfadiag or FiatEcuScan, if you have a laptop, self diag can be yours for around 60-70 bux.