I've heard of excuses in my life but NEVER heard this one

"Honey I really couldn't get home on time from the lake -- I couldn't get the engine to shut off" !!!!

I like it

Hope you get your issue solved..... i

3pointstar

Bup, my ECM is fried.

Thanks for the reply and sorry about your ECM being the problem

Like I said in POST # 6 half way down the page - 2 techs had 2 different problems - one engine would start on its own and the other engine would never shut off, both were ECM failures,

Some people and techs believe that ECM's really can not ever fail or it is so very very rare that they do.. And like I said never rule the ECM's out of the mix for being the problem child.

Thanks again for posting the problem..

I understand that every component is capable of failure, but I don't understand the cause. Should I be looking for serious defects? Or do they just occasionally go to ECM heaven?

And what is their failure mode? The engine runs, so WTH?

Internally of the ECM there is different drivers for a jist of this. Not all failed

Sometimes a bad ground or a shorted wire to a connection or J connection of the ECM can cause failures. Sometime failures can be termed as the ECM has a bad ground or lost its ground. Post # 9 also has other factors as well.

Something could have caused it or a rare ECM failure on its own.

Who tested your ECM for you ? A dealer and or a scan tool ? just asking.

Cole that just sucks for you after having the engine rebuilt and ecu tuned , what mefi does your boat have ?
on the other hand a 21rst century efi unit to go with the new engine...priceless! :cool-smiley-011:

Sorry to learn of the problem -- but at least you got it diagnosed. -- dumb question what does the ECM cost to replace-- are we talking a few hundred or thousands??

3pointstar

Crazy price for MERC OEM thru a dealer - MEFI 1, 2 and 3 NLA so you have to convert over to MEFI IV and harness adaption. Again going thru OEM and OEM dealer cost can range from 1800 bucks to 3000 bucks depending what he has.

You can get a reman one for a grand to 1500 bucks of MEFI 1 thru 3. Used 350 to a grand depending and used is used - works for a day or two or 6 months only - your lose.

My guess is he has MEFI 2 or 3.

double post

What is the process of just going to a new holly or similar system?