I had a letter about this in August.

"Your vehicle is now required to be installed with the very latest and improved engine calibration software. Software will also be installed to enhance the accelerator response as well as provide engine noise reduction".

This stinks of dieselgate - Mazda aren't going to be offering a free improvement in accelerator reponse and noise reduction, are they? So has anybody else had this done?

Yes I had it done supposedly  on a 2014 whilst in for a service. I cannot say it improved the performance nor did it improve mpg as compared to the same time last year when I was touring, so  long motorway runs , in other words.
If they improve the emissions then in most cases fuel efficiency suffers, so a bit self defeating in my eyes.
I will have to start using  Shell V or BP Ultra again see if the consumption improves.

Anybody else seen a detioration since the PCM upgade?
The other thing they were supposed to check was the blowing injectors, rather than reseat them with new washers and correct torque. They are waiting until it happens, causes damage to the engine , then expect you to pay for repairs. 

My Mazda 6 GH6 (2013 with 66,666 km on the clock) has suffered power steering failure.  It's the electro mechanical type.  The other day I was parking and all of a sudden the steering started to get really heavy so much so that I couldn't turn the steering wheel at all!  I turned it off and waited 5 mins and tried again and it worked but only for a minute and the same thing happened.  Brought it to my local indy garage who said there wasn't any known recalls of this type and so the only option was to have the whole steering unit sent to a place in Dublin (Ireland) for a refurbishment as a new Mazda unit would have been around €1800 excluding fitting.  Have to wait 2 weeks now for the part to be mended and returned to the garage for fitting so I'm looking at around €1200.  Has this happened anyone else?  Am I going down the right track here or is this something like a design flaw that Mazda should cover?  PS my front tires were wearing down crazy on the outside (not inside) if that might have anything to do with it like cause or effect.

Is it a clicking sound ?   If so it is more than likely to be your battery on the way out.   The clicking sounds are the relays trying to close to enable starting.

Yes it could be the starter motor.

The fuel filter needs replacing every thing service and checking for water at every service. I replace at every second service. I do not think this can cause any noise as the engine runs fine when it runs.

https://euroesi.mazda.co.jp/esicont/eu_eng/mazda3/20110724140058/html/id0110f2801000.html


Try the above link

To check it, take off cam cover, and No 1 injector, using a dial gauge ,or a long thin screwdriver through injector hole, determine TDC and see where mark is on EX cam.