Alfa Brera 2.4 JTDM - Strange noises and boost needle eratic
Ok so this has been going on for a while now and its so unpredictable I just cant put my finger on what it could be - can you help?
When you start the engine it is lumpy and cloud of smoke out of back when it fires up.
Starts perfectly with no smoke
Runs perfectly, pulls strong needle on boost guage is as expected and no noises.
Pulls strong, but probably not quite as good, boost guage reaches 1.5bar and stays there under full throttle but at half pedal it boosts and then drops but then boosts fine if pedal to metal. This is accompanied by a whooshing (dump valve sound) when it comes off boost.
Pulls string, boost guage reaches 1.5 bar but drops and boosts under anything but full (pedal to the metal) throttle accompanied by a growling/rattling sound on acceleration from just in front of passenger side dash.
Can anyone shed some light on what the problem can be and why its so erratic and unpredictable. It can be one or the other the same day but just a different journey. Even do one/two of the above during the same 20-30 mile journey
Thanks in advance