ECU failure - 156 GTA

[amrus1]

Hi everyone

It looks like my GTA won't start because there's no power getting to the injectors. I'm told it could well be an ECU failure.

Just looking to see from those more knowledgeable than myself what my options are...

- I hear Autolusso make an aftermarket ECU for approx $3K - any opinions on these?

- Is ECU repair an option?

- Is my GTA basically just spare parts now?

Many thanks,
AMR

[Citroënbender]

Hi, and first up...

DON'T PANIC

This could be a really, really simple issue.  Your first step is - assuming you're not especially hands on - to get it in the shed with someone who runs good diagnostic software.

Even if the ECU is crook, there are some forms of repair possible, else you can buy a donor ECU kit consisting of engine ECU, under-dash body computer, immobiliser chip. So long as you have one immobiliser chip, others can be "cloned". There's no change of the key blades or anything like that.

[amrus1]

Hi, cheers for the reply.

It's sitting with an alfa mechanic now, apparently no faults came up in the scan so trying to diagnose the issue by elimination.

And yeah spot on, not particularly hands on with this stuff. GTA engine bay has no space anyway so wouldn't know where to start.

Mechanic mentioned there's no power getting to the injectors and the potential ECU issue. Am bringing in the spare key, think he's looking to rule out immobiliser problems.

With the ECU stuff, he mentioned it could be potentially a $3K sort of outlay to get a one. Apparently they don't make new ones anymore.

Does that sound about right?

Thanks again

[Citroënbender]

$3K sounds a bit over the top.

I need to point out right now, my only Alfa exposure is 147 four cylinder models; there is a fair degree of electrical overlap with the 156 V6 but not 100%.

In the diagnosis, lack of immobiliser communication is usually a clearly identifiable issue with its own "fault codes". Checking every ground, the big fuses atop the battery (I'd be suspicious of these ones!), then the under bonnet fuse box and finally the under dash fuse panel is a good way to work diligently through these supplies.

With the V6, apparently one giveaway of ECU failure is if it will start and idle (poorly) with the motorised throttle unplugged.

[amrus1]

Thanks for the input.

The only other clue I can think of is that the car was starting to idle unevenly over the last month or so. I'd already intended to get it looked at in the next service prior to it not starting.

But yeah it would hold the normal idle, then dip the revs slightly for a fraction of a second then be fine and dip again. This would continue for as long as the car was at idle. It was certainly driveable but a little bit annoying. With the throttle open and driving above parking speeds it was fine.

Does this info shed anymore light do you think?

Any GTA owners/mechanics feel free to jump in as well

[poohbah]

I'm no expert on GTA issues, but it seems from this thread on UK site alfaowner that ECU failure is a (feared) recognised problem for the GTA. The replacement kit they refer to is priced at £1800, so $3k sounds like it probably is the market price.

Best of luck with the diagnosis - hopefully something simpler/cheaper.


http://www.alfaowner.com/Forum/alfa-gta/1080658-autolusso-gta-ecu-replacement-kit.html

[poohbah]

FYI - this may help you with diagnosis - from the same UK thread:


Also interested. What are the warning signs / symptoms of a failing ecu?
Flickering engine light when you turn the ignition on, throttlebody clicking in time with it. Engine won't start unless throttlebody unplugged.

[amrus1]

Thanks mate much appreciated. I've just gone through the Autolusso website but can't find the GTA ECU kit.....I've sent a quick email asking about it.
Cheers

[Citroënbender]

Informative reading:

http://www.alfaowner.com/Forum/alfa-gta/375231-147gta-diy-ecu-repair.html#/topics/375231?page=1

[poohbah]

Good find CB - that might be a handy starting point for Amrus' mechanic.

[Craig_m67]

.. you should talk to Bazz (on the spot Alfa).

as I understand it the GTA ECU can develop dry joints and issues with surface mounted components.  It can be fixed, replaced etc. 
As above there are lengthy threads and info on the interwebs about it (if you know to look obviously)

I wouldn't spend to much time with a non Alfa indie trying to diagnose this, you'll just be paying them to learn what others already know.

Craig

(edit) - i flicked him an email with a link to this thread.

[bazzbazz]

Ok, I have had to repair faulty ECUs many at time, the latest just last week.

1/ First of all what warning lights are on the dash when you turn key to ignition (MAR) ?
    All lights should go out except Engine, Battery, Oil & Hand Brake lights. If the dash is lit up like a Christmas tree with VDC, ABS &
    others, that's a sign of ECU failure.

2/ If the ECU fails you should NOT be able to connect to the ECU with diagnostics

3/ To confirm its the ECU simply disconnect the Throttle Body cable, it's the connector that goes to the Throttle Body and is just under the
    mouth of the Throttle Body. Once the cable is disconnected you should now be able to start the car easily, there will just be no response
    from the accelerator pedal.

If the 3 above indicators are not present then it may not be the Engine ECU, if all 3 ARE present then it is guaranteed that the ECU is FUBAR!

[Citroënbender]

Has any progress been made? 

[Mick A]

I like how there's been three separate mentions of disconnecting the throttle body to see if it starts, and he still hasn't listened or responded to it.

You'll also probably hear a whining sound from the throttle body when the plug is still connected, this is a dead giveaway of a back-feed through the circuit and means the ECU is dead.

Hopefully you'll take on board some of this useful information.

Mick.

[amrus1]

Hi all very much appreciate everything that's been written here. I've just logged back in after a crazy week, apologies if that came off as unappreciative. Not much I can do given it's sitting with my alfa mechanic, though I have directed him to some of the info here as a potential help.

So the update:

There were no fault codes, crank sensor seemed fine. Attempting to start the car with disconnected throttle body was on the list of things to do but my mechanic wanted to do a few other checks first. He basically disconnect a lot of the electrics, checked fuses etc, nothing overtly wrong that he could see.

BUT

When he re-connected everything and turned the key the engine started! As if nothing had ever been wrong....

So that leaves another problem, that is, what was the original problem to begin with?

My laymans instinct reckons it's something to do with the sheer amount of heat the GTA engine bay generates. I recently learned that this heat actually gets worse after the car is turned off and that explains, why in the past, attempting to start again after a drive has sometimes been difficult. Once it cools down it would start first time.

Does that give any clues?