Alfa Romeo Owners Club of Australia Forum

Technical => 939 Series (159, Brera and Brera Spider) => Topic started by: cogitare on July 13, 2020, 06:34:58 PM

Title: Brera 2.2 - all 4 plugs badly carbon fouled
Post by: cogitare on July 13, 2020, 06:34:58 PM
Hi all.  I have decided to see if any of the brilliant forum members can help, having used similar forums for my Jag.

My wife owns a 2006 2.2 Brera.  It has about 80k on the clock, and has been properly serviced in Melbourne before she acquired it and gave it a new home in Canberra.

The Issue.
All four plugs regularly develop a heavy carbon fouling, eventually stopping the car from starting.  There are no error codes.  It has spent time and plenty of $ with 2 different mechanics and over time has had most of the components usually associated with such behaviour replaced to no avail.   Coil Pack (x2), PCV Valve, all 4 O2 Sensors, MAF sensor, and lastly in desperation the ECU Cloned (with an identical unit) and a second hand Throttle Control Body (lovingly cleaned by me).

The 2 mechs found no leaking hoses or other common sources of the issue.

If you replace or clean the plugs, when you first start the engine it often fails to start first press, then on the second will rev for less than a second then chug and spit and eventually run.  The more you use it,  fouling is inevitable - equally on all four plugs, and then she's dead.

I have searched this forum and others with little information relating to this issue.

I know more about motorcycles and Jags than Alfas but happy to learn.

I am hoping one of the Alfa experts out there may have some suggestions as to why this damn thing is running so rich.

Thanks in advance.  Silvio.
Title: Re: Brera 2.2 - all 4 plugs badly carbon fouled
Post by: bonno on July 13, 2020, 08:53:19 PM
Hi Silvio
Could be a faulty fuel injector/s. Find attached a simple test using a screwdriver and using it to listen for ticking noise (refer to attached Youtube video). This technique I use to tune multiple carbies and works brilliantly.
https://www.youtube.com/watch?v=tA_E6X4ISgQ

Title: Re: Brera 2.2 - all 4 plugs badly carbon fouled
Post by: Colin Edwards on July 14, 2020, 11:43:21 AM
Possibly thermostat stuck open causing engine to run too cool?
Possibly coolant temperature sensor way out of range / open circuit stooging ECU into thinking engine is always very cold?
Has anyone stuck a CO sensor up the exhaust to measure what's coming out?
Correct heat range plugs?

Jump on the alfaclubact.org.au site and look up "Alfa Romeo Service Agents - ACT".
Title: Re: Brera 2.2 - all 4 plugs badly carbon fouled
Post by: Mick A on July 14, 2020, 08:17:15 PM
Yeah really common on the 2.2 JTS.

How long would you say your plugs last before fouling?

Mick.
Title: Re: Brera 2.2 - all 4 plugs badly carbon fouled
Post by: Ascari32 on August 28, 2020, 06:25:13 PM
Quote from: cogitare on July 13, 2020, 06:34:58 PM
Hi all.  I have decided to see if any of the brilliant forum members can help, having used similar forums for my Jag.

My wife owns a 2006 2.2 Brera.  It has about 80k on the clock, and has been properly serviced in Melbourne before she acquired it and gave it a new home in Canberra.

The Issue.
All four plugs regularly develop a heavy carbon fouling, eventually stopping the car from starting.  There are no error codes.  It has spent time and plenty of $ with 2 different mechanics and over time has had most of the components usually associated with such behaviour replaced to no avail.   Coil Pack (x2), PCV Valve, all 4 O2 Sensors, MAF sensor, and lastly in desperation the ECU Cloned (with an identical unit) and a second hand Throttle Control Body (lovingly cleaned by me).

Hi!

The engine could be running rich - what is the economy like? Inspect the Lambda probes - the plastic tubes around the wires should be free to allow air to get to the Ports into the Lambda bodies. This is to reference exhaust gases sensed against. Alternatively - MAF issues?, AFR map in the ECU or even Lambdas on their way out.

I need to get my 3.2 AFR checked as she is, according to some - running rich. However, still getting "Relatively" good economy. 

The 2 mechs found no leaking hoses or other common sources of the issue.

If you replace or clean the plugs, when you first start the engine it often fails to start first press, then on the second will rev for less than a second then chug and spit and eventually run.  The more you use it,  fouling is inevitable - equally on all four plugs, and then she's dead.

I have searched this forum and others with little information relating to this issue.

I know more about motorcycles and Jags than Alfas but happy to learn.

I am hoping one of the Alfa experts out there may have some suggestions as to why this damn thing is running so rich.

Thanks in advance.  Silvio.
Title: Re: Brera 2.2 - all 4 plugs badly carbon fouled
Post by: bazzbazz on August 28, 2020, 07:10:05 PM
cogitare - May I ask where you got your ECU cloned, my ECU guy has retired.