How do I reset my Alfa Romeo ECU?

My GT 2.0L JTS has been idling a bit rough recently, and it felt like a few of my horses had flown south for the winter. In addition, my climate insisted on only blowing hot air, no matter what temp I dialled in.

Having trawled through various threads, the ECU reset fix was mentioned several times as a cure for both symptoms.

So, today being a quiet day in the Christmas break, I decided to attempt the ECU and throttle re-set procedure -which is as follows if you haven’t seen it in other threads :

Disconnect battery for 45 mins
Reconnect battery, and turn ignition to MAR for 90 secs
Turn off and leave 90 secs
Start engine WITHOUT pressing throttle and let the car idle for 15 mins (I repeat, do not touch the throttle whilst the car is idling)
Turn engine off and leave for 10 minutes
Start the car and go for a drive, using a number of styles (eg town, motorway, thrash etc)

It nearly cured the climate problem (well it blows a bit cooler) so if anyone has any tips on how to fix, let me know.

But the cherry on the icing on the cake was something I didn’t expect, it seems to have cured my ‘stepping’ driver’s window problem that I had given up on !!

Now the driver’s window goes up and down as smoothly as the proverbial baby’s bum.

So, if you’re thinking of trying the ECU/Throttle reset and you have an hour or two on your hands this festive break, give it a go — it might work miracles for you too!

105 příspěvků · Připojeno 2006
THANKS i haven’t heard of that.
1406 příspěvků · Připojeno 2002

My 156 JTS is idling a bit roughly, especially with the climate/aircon on. Will give this a try when it’s a bit warmer and drier outside to see if it improves things.

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Děkujeme za zaslání tohoto příspěvku.

My Alfa History: 1983 Alfasud Sprint Speciale, 1999 145 Cloverleaf (QV), 2001 156 2.0 TS, 2003 156 2.0 JTS
My Current Alfa: 2005 GT 3.2 V6

480 příspěvků · Připojeno 2009

does it work on the JTD engines too, as mine performs o.k, but ticks over a bit rough, also when ticking over it smells a bit rich at the exhaust, not sure if thats normal or not, as only had the car two weeks.

422 příspěvků · Připojeno 2009

Made quite a difference on mine so worth doing IMO.

Just make sure you have the radio code if yours needs one.

If you chase the answer, it moves away.

When I did it on my 2.0 TS it was a complete disaster but in a good way. I had my doubts about the MAF so did the reset and, following the reset, it packed up completely. New MAF, job done.

1321 příspěvků · Připojeno 2001

It nearly cured the climate problem (well it blows a bit cooler) so if anyone has any tips on how to fix, let me know.

Odpojte baterii
Počkejte pět minut
Reconnect battery
Wait five minutes — ignition OFF. You’ll hear the air control flaps operating during this time — this is a self-calibration routine and gets buggered up if you switch on too soon — wait for silence.

«Diesel — Green Fuel of the Future» — Lucas Diesel Systems slogan circa 1992

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SteveD GT Discussion starter
61 příspěvků · Připojeno 2009

Thanks Simon — that’s tomorrow’s project sorted !

Will let you know how I got on.

9 příspěvků · Připojeno 2009

hi there, i have a 156 2.0ts and although its idling ok it just doesn’t have any get up and go, had the car four weeks now and i’m already smitten. the book says 165bhp but it definately feels alot less. do you think this would work to put the sting back in its tail? and if anyone has any other suggestions could you please please help me?

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Je Bentley pod BMW?

5696 příspěvků · Připojeno 2005

Are you sure about those figures, I’m sure the 2.0 has 155 on the 156 .
And it depends on the engine/year.
If its a JTS expect it to be down a bit, possibly as low as 140.

5624 příspěvků · Připojeno 2009

Having trawled through various threads, the ECU reset fix was mentioned several times as a cure for both symptoms.

So, today being a quiet day in the Christmas break, I decided to attempt the ECU and throttle re-set procedure -which is as follows if you haven’t seen in other threads :

1. Disconnect battery for 45 mins
2. Reconnect battery, and turn ignition to MAR for 90 secs
3. Turn off and leave 90 secs
4. Start engine WITHOUT pressing throttle and let the car idle for 15 mins (I repeat, do not touch the throttle whilst the car is idling)
5. Turn engine off and leave for 10 minutes
6. Start the car and go for a drive, using a number of styles (eg town, motorway, thrash etc)

So I did this, and my GT is reborn ! Faster, smoother, more torqier, even idle — it’s bloody fantastic ! I can’t believe how different the whole car feels.

It nearly cured the climate problem (well it blows a bit cooler) so if anyone has any tips on how to fix, let me know.

But the cherry on the icing on the cake was something I didn’t expect, it seems to have cured my ‘stepping’ drivers window problem that I had given up on !!

Now the driver’s window goes up and down as smoothly as the proverbial baby’s bum.

ČTĚTE VÍCE

How do you check a clogged washer drain hose?

So, if you’re thinking of trying the ECU/Throttle reset and you have a hour or two on your hands this festive break, give it a go — it might work miracles for you to !

The information contained in this post was extracted elsewhere online and is included here for my easy reference as well as a follow-up instruction to some of my other posts. I do not take responsibility for any problems you may encounter running the steps below, but I have personally gone through all the steps myself with my car without a hitch.

In any case, please proceed at your own discretion. The following steps apply to cars under the Alfa Romeo make.

how to reset ECU and throttle

How to Reset ECU and Throttle

There are 2 methods to reset the ECU and throttle:

Examiner Method

The first is by using an Examiner. The Examiner is a RM20,000 (or more, depending on pre-installed features) large handheld computer running on Windows which allows you access to the car’s ECU to perform various checks and on-board diagnostics (OBD), all via the OBD connector below the driver’s dashboard. Given the cost, not all mechanics own this Examiner. My regular mechanic does. So does the marque local distributor’s workshop. Provided you can get to someone who owns an Examiner:

Get the mechanic to connect the Examiner to your car’s OBD port and reset the ECU. This option appears as a selection on the Examiner’s touchscreen.
Start the engine but Do NOT touch the throttle and rev the car just yet. Leave the car running idle for 15 minutes, otherwise the car will not rev freely later.
Turn the engine off and leave the car for 10 minutes.
Start the engine and take the car for a drive. Rev the engine a little on your way out!

DIY-Manual Method

The second method is what this article is all about – do it yourself. To manually reset the ECU:

Pop up your bonnet and disconnect the negative lead from your car battery. Leave it disconnected for no less than 45 minutes. You may also choose to leave it disconnected overnight if you prefer, so you can start first thing in the morning. Sometimes I do that.
NBThere’s a quicker way to reset and clear residual memory and charge, and it involves disconnecting both positive and negative leads and shorting across these leads. The effect is immediate and so there’s no 45-minute wait. A word of caution though: Shorting can be dangerous. Not sure if you could potentially fry your ECU, but if you accidentally or carelessly short the battery terminals instead, it could lead to an explosion. My advice: Stick with the 45 minutes. That’s what I do.
After 45 minutes, reconnect the negative lead to the battery terminal.
TO PERFORM A THROTTLE RESET, PERFORM THE FOLLOWING 2 ADDITIONAL STEPS AT THIS POINT. IF YOU DO NOT WISH TO RESET THE THROTTLE, PROCEED WITH STEP 4.
- Put the car key in ignition, turn to MAR and leave it in MAR for no less than 90 seconds. This is when your dashboard would come alive. DO NOT start the engine!
- After 90 seconds, turn off the ignition, but DO NOT remove the key and leave it in the key slot for another 90 seconds.
Now, start the engine but DO NOT touch the throttle just yet, and just let the car remain idle for another 15 minutes, otherwise the car will not rev freely later.
Turn the engine off and leave the car for 10 minutes.
Start the engine and take the car for a drive. Enjoy revving the engine on your way out!