156 2.0 TS cold starting issue

[imrejanosi]

Hi everyone,

I hope someone has experienced exactly the same issue and can point me to a direction to find out what is  exactly wrong with my Alfa 156

The car:
1999 Alfa Romeo 156 2.0 TS manual
Around 226000 km

The problem:
It developed more than 3 years ago but so far I was unable to resolve it. It did not get worse so I was not desperate to fix it.
Every morning when I cold-start the car it fires up then 9 out of 10 times it does the following:
Engine starts to shake, noise of the car sounds like it only runs on 2 or 3 cylinders (RPM falls to around 500 RPM from normal IDLE around 800-1000 RPM). Pressing the gas pedal either stalls the car or engine does not rev up at all (sometimes it revs up but struggling to move from IDLE). After 10-15 seconds or after a restart it sounds normal but when I put it into gear and try to roll out from the parking spot it starts again. (Sometimes the shaking and strange noise only starts when I put load onto the engine like when I try to pull out from the parking spot, not when it IDLEs after a start. No power from engine, shaking and sounds like 2 or 3 cylinders running only. It either stalls or I have to rev up and keep the engine running on higher revs (3-5k RPM) for 5-10 seconds (sometimes it does not react to gas pedal at all but sometimes it slowly revs up). This could happen 2-3 times while I get out of the carpark or maybe at the first traffic light in the first 1-3 minutes. At the first few minutes it feels it has less power and struggling to take off at the lights then suddenly the power is back. After this the car drives and starts normal all day. It is only a problem when I start the engine rock cold.

It feels like some sort of starvation, fuel, air or sparks probably caused by some faulty sensor somewhere. Sometimes the shaking and strange noise only starts when I start to put load onto the engine like when I try to pull out from the parking spot not when it IDLEs after a start.
On the dashboard when the engine is shaking and down to around 500 RPM and on the edge of stalling the battery sign is flashing up few times. (I don't know if it is the cause or symptom of almost stalling) Maybe I have a faulty coil pack that only plays up when it is cold?
I plugged onto my laptop when this happens but it has never thrown an error message. Connection is OK because I can read engine parameters. Alfa service did not find an error message either.
(Alfadiag and MultiECUscan software)

So far:
-cleaned MAF sensor
-installed new air filter
-re-calibrated throttle body butterfly opening value (by an Alfa specialist garage)
-reset self-adjustable values through computer
-replaced all spark plugs and cleaned all spark plugs inlets and connectors + coil pack tubes

Anyone had this issue? The problem is not getting worse, but it is annoying every morning and I don't really like revving the engine high when it is rock cold to stay it running.

Thank you everyone,
Imre

[Mick A]

I would replace the MAF sensor. It doesn't always work again after cleaning it. Sometimes it just needs to be replaced.

Cheers,

Mick

[Citroënbender]

One of mine has dependably chugged and staggered from a "dead cold" start for several years. I'd assumed it was a minuscule head gasket leak wetting up a plug. No overheating when hot and it has a 20K old Bosch MAF that changed nothing. Haven't been too fussed as temperature remains stable and coolant loss about one dessertspoon a month.

[imrejanosi]

I would replace the MAF sensor. It doesn't always work again after cleaning it. Sometimes it just needs to be replaced.

Cheers,

Mick

Hi Mick,

Thank you. I actually missed to add that part. I already replaced with geniune Bosch MAF sensor after the cleaning didn't help.

[imrejanosi]

One of mine has dependably chugged and staggered from a "dead cold" start for several years. I'd assumed it was a minuscule head gasket leak wetting up a plug. No overheating when hot and it has a 20K old Bosch MAF that changed nothing. Haven't been too fussed as temperature remains stable and coolant loss about one dessertspoon a month.

Thank you, yeah it sounds a similar issue. Apart from the morning annoyance it is not overheating or loosing coolant. Once it was misfiring and I found water around one of the spark plugs but I cleaned the intake tube and connectors and replaced the spark plugs. It solved the misfiring and it is not wet anymore but the original issue is stubborn as.

[imrejanosi]

Just an update. The problem has never been resolved. I just live with it and stop spending money to rectify this issue. It is a 20 years old car after all. Despite the cold start issue the car still drives fantastic.
We tried:
-New MAF
-Cleaned throttle body
-New Coilpacks
-Clean Sparkplugs
-New Fuel pump

[Colin Edwards]

Does the engine consume coolant?  Do you need to very occasionally top up the coolant levels?

A head gasket with a TINY leak may allow coolant to weep into the cylinder.  When the hot engine stops, the pressurised coolant enters the cylinder and vapourises.  As the engine cools, the coolant vapour will condense on the piston head, cylinder walls, combustion chamber, valves AND SPARK PLUG.  The surface that cools the quickest or the object with the least thermal inertia will collect the greatest amount of condensate.  Spark plug electrodes will cool relatively quickly in a stopped engine.

The condensed coolant MAY be in high enough concentration to short the plug electrode to earth - no spark!  As the engine warms up, the condensed coolant evaporates and eventialyy the plug fires correctly - no engine issues while hot!!

Worth considering.