Here's the story, 2003 motor, ran the serial number on the PCM, there have been "7" upgrades on this model PCM and my serial number had not one of them. Spoke to my Merc Master Tech in S.C. who researched the PCM S/N and he'll get Merc to reflash it to the latest revision. Soooo that being said, it's on it's way to S.C. to be shipped to Merc (thru an authorized dealership). About 2 weeks is what I'm told to turn it around.......I'll report back when its back on the motor and the first time out with the reflash.

I was told the same thing about factory tunes , there have been several tunes after mine.Keep us updated as to turn around time and how the boat runs after. I believe that Whipple is one of if not the only "Authorized" shop to re-flash/program Mercs ECU'S

I finally got a reply back from Dennis @ Whipple on their PCM reflash, Stage 2 = $745, that's allot of coin for soot control and a only 5 to 8% gain in power. I'm gonna look at it this way, Merc's reflash is free, so why not. If I'm still not satisfied the Wipple reflash may have to be done...............time will tell.

I believe they run a little fat to err on the side of reliability. The soot will wipe right off a freshly waxed transom and if it doesn't then vinegar makes fast work of it.

You'll be better off with the latest Merc cal in terms of soot control. Glad to hear Merc taking care of you. I reviewed my Whipple tune in a post on this forum last may if interested to read.

I kinda looked at it this way: Merc reflash=$000.00/ $40.00 shipping; $40.00 out of pocket
Whipple Stage 2: $745 + $40.00 shipping; $785.00 out of pocket

Pretty much a no brain'er for the time being. I'll give your Whipple post a look-see this evening.

Thank you

My engines are also 2003. After I had the reflash done it cleared up at least 80% of the soot. Also only use 87 octane.

Here's the cleaner I ordered, once I get back on the water we'll see how it works. I'll report back in about 2 weeks.

+1.
Wipe off the majority with a towel as soon as you pull the boat out helps a lot also.

Update:

PCM is back after a Mercury Reflash to the current revision for this motor/PCM combination. About a 2 week turnaround for the reflash.

Haven't been on the water since the reinstall, weather has been horrible here. I plugged in my laptop (running the RINDA DIACOM) to the PCM Diagnostic port and found no codes other than the normal "GHOST CODES" for sensors that are not on the motor, this way I know I'm starting out with a clean slate. As soon as I'm able to get out, I'll report back on results of the reflash addressing the "SOOT" problem, as an added benefit I was also told there has been an improvement in the PCM controlled timing on the motor.

Thanks all for sharing your information......