ECM for 2002 Merc 350 Mag MPI Towsport

[lilhuff]

I am bringing back a 2002 Ski Centurion that the back half of the boat sank in shallow fresh water and I have a question about the ECM (Engine Control Module). I know you can send ECM's for cars to be flashed for performance upgrades but can you also test a boats ECM to make sure that it is still good? Also if the ECM is bad what are some alternatives other than paying the $1800 for a new Merc ECM? Are there after market EFI systems that would possibly boost performance and allow you to replace the ECM with a non Merc? Are there after market ECM's that work as well?
Any information would be greatly appreciated.

Thanks,
Lilhuff

 

[lilhuff]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

I know this might be a unique situation but does anyone have any ideas?

Thanks,
Lilhuff

 

[Dshow]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

To start, you round up a scan tool to see if the ECM can communicate. (Any service shop will have one or they can be bought for a couple hundred buck...) If it talks, you can start fixing the faults it displays and then start checking out the spark, fuel/fuel pressure, and/or compression. If it won't talk, your back an ground zero.

Did water get in the engine? Does it turn over?

 

[lilhuff]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

Water did get in the engine but it is not locked up it was at the dock not running when it sank. It cranks over easily and I was able to drain and clear all if the water jackets. It cranked easy enough to fog the engine and actually acted like it was going to fire on a light hit of starting fluid. I will see if I can borrow a scan tool or go ahead and purchase one. Are there any scan tools recommended for boat motor packages or will any ODBII scanner work. I would like to get one that will work with a laptop and allow me to make changes.

 

[Bondo]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

Water did get in the engine but it is not locked up it was at the dock not running when it sank. It cranks over easily and I was able to drain and clear all if the water jackets. It cranked easy enough to fog the engine and actually acted like it was going to fire on a light hit of starting fluid. I will see if I can borrow a scan tool or go ahead and purchase one. Are there any scan tools recommended for boat motor packages or will any ODBII scanner work. I would like to get one that will work with a laptop and allow me to make changes.

Ayuh,... Feed it some gas, 'n See if she'll Light.... It might be alright, 'n ready to Go...

As far as I know, the Merc ecm is a Mercruiser thing...
I believe you need the Rinda reader,...
I've heard that Only a factory Rep can do anything with it's programing...

 

[Dshow]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

Rinda makes a tool for Mercruiser. Before you run out and buy a tool, understand what ECM you have and make sure the tool interfaces with that module.

 

[lilhuff]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

It is a Mercruiser ECM-555. After doing a little research I did not find any kind of after market replacement. It also looks like you may not be able to read the ECM with a standard scan tool. I was hoping someone has been able to read the unit with a standard scan tool.

 

[Dshow]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

I have never read the 555, but I believe my tool came with an adapter for the 555.

Update: It support the 555. Check out this link to the manual:
http://www.rinda.com/acro/merc_manual_v6.pdf

 

[Don S]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

It is a Mercruiser ECM-555. After doing a little research I did not find any kind of after market replacement. It also looks like you may not be able to read the ECM with a standard scan tool. I was hoping someone has been able to read the unit with a standard scan tool.

No on both counts, it takes a marine scan tool to read the 555. The rinda scan tool Dshow referred to is about the least expensive tool you can get. But, it is full featured. I actually use it more then the laptop. I get the same results (although a bit slower) as the laptop and you can actually see it and use it out in the sun. They are are $400 new and cover many of the IO manufacturers. Here is a link to it.

http://www.rinda.com/marine/mtspec.htm#techmate

 

[Dshow]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

Just a thought, when you key on but before you crank, do you hear the fuel pump running for ~2 seconds?

 

[lilhuff]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

I have not tried to start it for several weeks. I do not remember hearing the fuel pump. I did replace the solenoids to the left (forward) of the ECM because they looked like they had water in them at one point and one was chattering when you turned the key. The boat is in storage now and I would like to verify if the ECM is good, rebuild the starter, go through the alternator and do whatever I could prior to winter getting here. I figured I could pull the starter, alternator and anything else someone might suggest and work on them in my garage during the cold months. I have drained all of the oil filled it back up and cranked it over to fog the intake and cylinders and then drained the oil. I also drained the transmission fluid. Is there anything else I should do prior to storing for the winter? Does the ECM have to be in the baot to be tested?

 

[dubs283]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

why do you need to test the ecm?? did it get wet??

if so, i hope you immediately dried it!! -even then i would be suspect of it working properly

does the engine run?? sounds like all you have done is turn it over??

i would not put a boat away for winter after it sank hoping it is okay without completely going through all systems and verifying the engine runs and is sound

the only way to test the ecm is to have it connected to the engine in the system so a cds or other scan tool can communicate with it

 

[Dshow]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

I would definitely get it running prior to winterization... You may have more issues than what you've got if you leave it until spring. Having the ECM in the boat will checkout the whole system, not just the ECM, so I would leave it in the boat. I would also do some troubleshooting and not replace parts that look like they got wet.

There is a sticky on winterization, I would definitely read it if you're doing it yourself.
http://forums.iboats.com/showthread.php?t=178695

 

[Tail_Gunner]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

There is very little aftermarket support for marine efi. If you want to change the 555 system you will need to rewire the engine. Yes there are aftermarket options avaible...But by the time your done it will more than probably cost more that replacing the 555

Really to bad thats not a mefi system there is support for that product but it would be cost prohibitive for a switch over i believe. Below is a link

http://www.obd2allinone.com/sc/toplevel.asp?cat=0

Be careful if you select anything other than a marine ecm.

 

[lilhuff]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

Thanks for all of the input. I am going to bring it back to my garage this weekend and see if I can get it to run. I will probably have questions once I get started.

 

[lilhuff]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

Well I brought it back and put a fully charged battery in it. I could not get the starter to turn over. The slave solenoid clicks over and I have voltage to the starter solenoid but can't even get it to crank by jumping across the starter solenoid. Took it off and it definetly got wet. It did turn over in the spring but it was hit or miss. I am going to replace it. Has anyone had any experience with Sierra starters. I found one for $149 and the least expensive Quicksilver/Merc I could find was $169. I found a bunch of remans and off brands but do not want to go with a brand I have never heard of.

As for the fuel pump I did not hear it come on and with the ingnition on there is no voltage to the fuel pump. It looks like I will have to take it somewhere and check the ECM. Any other suggestions would be greatly appreciated.

 

[Tail_Gunner]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

The ecm is the last thing you need to check out...The very fact that the fuel pump charged and shut off that is a indication it is working...Something told it to cut off..aka fuel pressure.

 

[Dshow]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

If you do not have an Merc Service Manual for the engine, I would recommend getting one here -> http://www.4shared.com/dir/8iGasxP0/sharing.html while they are available... Looks like manual 31.

It should have wiring diagrams to help troubleshoot the fuel pump issue. When the key is turned on, the fuel pump should only run 2 seconds then shut down without the engine running... Were you measuring the voltage when the key switch was cycled? It could be the ECM is not commanding the fuel pump on due to other issues.

Good luck!

 

[lilhuff]

Re: ECM for 2002 Merc 350 Mag MPI Towsport

OK I have finally had time to get back to the boat issue. I have since replaced the ECM, fuel pumps, igniton coil and controller, plugs, checked compression great in 7 cylinders and a little low in 1 but still within 30% of highest which is 200psi.
I borrowed a laptop and mercruiser program from one of the local marinas and here is what the code faults are:
16 MAP Sensor circuit low
94 Pitot Pressure circuit low
85 Oil pressure circuit low
75 Fuel level 1 circuit high
121 TPS 1 circuit low
130 trim sensor circuit high
The diagnostics on the computer reads 40psi for oil pressure with the key in the on position. I still can't get it to fire. I ran down all of the voltage checks and continuity checks in the manual and everything looks OK. I had voltage and continuity everywhere. I still can't get a spark out of the ignition wire from the coil to distributor. I am taking a lead from the post and taking it to ground and get nothing.
Any ideas would be greatly appreciated.