2004 2.0 JTS 156 - Motor Control System Failure - Fixed!!!

156southpaw · February 24, 2009, 11:10:29 PM

Hi guys - new to this forum - really valuable resource for all Alfa owners.

I thought I would share my experiences with the dreaded Motor Control System Failure on my 2004 156 JTS.

For several months I have been experiencing intermitent Motor Control System Failure warnings - probably once a week under reasonable acceleration (typically around 3000 rpm I would see the message - although only occasionally). In the past 6-8 weeks the problem become significantly worse - I was getting at least dozen warnings per day (they all seemed to self-clear from the computer within a few seconds). At the same time, I was noticing a loss of power (like the car was running lean or losing ignition) under any sort of acceleration beyond 2500 rpm (in any gear). The past 2 weeks have been bloody aweful - I was really struggling to accelerate without a warning message coming up and the car was shuddering and seemed to be running very lean (like it was running out of fuel).

The car went through a regular service and I asked the mechanics to check the fault codes on the computer and see what was happening. As the faults self-cleared, nothing was lodged in the system. I convinced myself that the service/tune-up would fix the problem (yes I know I was an idiot

) and I happily drove away from the dealer hoping never to see the dreaded Motor Control System Failure warning ever again.

About 2 kms into my trip home the car shuddered and lost a lot of power again and a permenant warning came-up on the computer for a Motor Control System Failure. This warning did not self-clear and I returned to the dealer to plug in the diagnostic interface. Low-and-behold, the failure was finally diagnosed.

Misfire on Cylinder 4 - the coil pack sitting on top of spark-plug 4 had died (verified using a multimeter - complete loss of impedience - hence no sparking (or very little) and therefore the car was running on 3 cylinders at times). After 1 hour (& ~$500

) - problem completley fixed.

I took my baby for a spin and she ran like a dream - absolutely perfect acceleration and all her power was back to normal. God bless the new coil-pack.

The dealer told me that this is becoming a common problem for the JTS engines (which I've confirmed through my reading of various websites).

Hope this info helps other JTS owners should they experience similar problems.

sivakshanmugam · March 15, 2009, 11:41:58 PM

Hey i'm a newbie too!! I had the very similar issue with my 2004 156 JTS and they ended up in changing my coil pack. But mines was different to urs, cos i had problems with cylinder 1,2 and 4. u could imagine how much trouble i would've gone through. Luckily mine was under dealer warranty and i didn't have to pay anything. The mechanic told me its a common issue for JTS. It runs very well after its been fixed. Guess can only hope for the best. Fingers crossed!

John Hanslow · March 16, 2009, 12:15:37 PM

Thanks for the info.

It appears that the Twin Spark and JTS have slightly differing issues in this area so the update is appreciated.

Cheers.

Stephen Aarons · March 18, 2009, 08:34:59 PM

Our 156 Jts has had 3 coil packs changed....one to go! haha.

156oro · June 07, 2009, 09:57:17 PM

Hi.

I had the same code come up on our 2004 JTS.

It happened when my wife ran the cal low on fuel.

The mach plugged it in & cleared the errors, but if it is coil or ignition pack then I suspect it may occour again (been good for over a week now.)

Mine has 86K on the clock...what K's did it start happening to yours?

156southpaw · June 15, 2009, 10:00:58 PM

Quote from: 156oro on June 07, 2009, 09:57:17 PM
Hi.

I had the same code come up on our 2004 JTS.

It happened when my wife ran the cal low on fuel.

The mach plugged it in & cleared the errors, but if it is coil or ignition pack then I suspect it may occour again (been good for over a week now.)

Mine has 86K on the clock...what K's did it start happening to yours?

Mine started at 70,000. Since I changed the coil pack, it has been a dream - perfect performance again.

saratoga · June 30, 2009, 04:52:44 PM

Me too! I had 3 coils go within 5000k of each other from about 50,000k. Very common problem but freaks you out when the message come up! I wonder if they were all originally fitted with dud coils and our replacements might be of better quality. Clicked over 100k last week and no further problems so far.
Steve

Davidm1600 · June 30, 2009, 05:11:24 PM

Ah, well then lucky me as my '03 156 JTS Sportwagon hasn't yet suffered this issue. The only fault to date I have encountered (touch metal !) is a faulty crank sensor which basically stopped the car dead. Had this fixed, $240 and alls fine once again.

Will keep an eye out for this other possible delight and should it occur at least I will be aware of the problem. Good to know. Dave

156southpaw · July 13, 2009, 10:31:37 PM

Quote from: saratoga on June 30, 2009, 04:52:44 PM
Me too! I had 3 coils go within 5000k of each other from about 50,000k. Very common problem but freaks you out when the message come up! I wonder if they were all originally fitted with dud coils and our replacements might be of better quality. Clicked over 100k last week and no further problems so far.
Steve

I actually wondered that too - I've read the same thoughts on other Alfa forums. Mine has been great since the initial problem (fingers and toes crossed

).

ForzaSab · July 16, 2009, 07:10:24 AM

Quote from: Choderboy on July 13, 2009, 10:58:10 PMDO NOT attempt to drive it at all. The computer gets all sorts of messed up readings on AF ratios and all that stuff which I know little about, but I could smell something burning when I ran ours on 3 cylinders and opened the bonnet to find the entire exhaust manifold was GLOWING RED HOT!

That's interesting because when my 3rd coil went i took it to Euromarque (Alfa dealer in Brisbane) and after they ran some computer checks they told me that it was ok to drive the car. They also charged me $750 ($396 for the coil) to fix the 2nd coil that went as apposed to a euro mechanic that only charged me for the part $340 odd and fitted it in a few minutes.
@ 156southpaw i too nearly filled my pants when i had this failure appear on my dash!

Simon Aarons · July 16, 2009, 10:42:21 AM

QuoteThat's interesting because when my 3rd coil went i took it to Euromarque (Alfa dealer in Brisbane) and after they ran some computer checks they told me that it was ok to drive the car.

I find that interesting they said that but no surprise there with the Dealer charging double!!!!!

John Hanslow · July 16, 2009, 12:24:08 PM

Good info guys, but how much to fix per coil ?

So should you go the set when one fails, you replace the lot or is that going overboard ?

Cheers.

ForzaSab · July 16, 2009, 05:48:11 PM

I was told (by Euromarque

) that if number 2 coil went for example that number 3 would follow not long after that due to it being quite hot there in the middle.
I Just replaced one at a time as i was strapped for cash at the time, as i said Euromarque charged $390 as apposed to $340 at Euro Aus.

156southpaw · July 16, 2009, 10:36:21 PM

It cost me $500 to replace my coil pack (took about 1 hour to replace). It has been >6 months since I replaced it and I've had absolutely no problem with the other ones (touch wood).

It would seem sensible to replace the lot if you could afford it - but my boss lady would throw a wobbly if I did that!!

John Hanslow · July 17, 2009, 01:11:02 PM

Thanks for the info. I can see why you would only replace what you have too.

$1200+ one go is a bit unnecessary.

The JTS is a superb motor, but besides the belt change issue, we have the irregular oil usage & coil problems, I can see that even a few Alfa service providers recommend the post 2002 V6 with extra safety, stability control and a better engine; or as cheaper alternative go for pre 2002 twin spark.

Cheers.