ECM Issues? Can someone set me straight.

[Bouyhead]

96 PS 190 275 TBI.Started the season with a rough idle after reaching operating temp. Over the course of two months read every post i could find,(thanks to all especially JimN and EngineNut) Checked for trouble codes,base timing, fuel pressure, compression, spray pattern, etc. Checked all engine sensors as per Indmars instuctions. Condition eventually gets worse were the engine would stall and be hard to start,(engine straining to crank). Go to the local dealer while on vacation he scans the engine and finds the timing at full advance after it stalls. There way backed up with work to go any further so I'm back on the phone Indmar.They tell me it's either the ignition module or the ECM. Put in ignition module, no change. Bypass the computer so the timing is controled by the ignition module still no change. I'm pretty stumped. Engine starts and runs fine otherwise and has plenty of power. Condition will rear it's ugly head ONLY after being at operating temp. for at least 15-20 min.
Sorry for the long post guys. Any input would be really appreciated.

[JimN]

96 PS 190 275 TBI.Started the season with a rough idle after reaching operating temp. Over the course of two months read every post i could find,(thanks to all especially JimN and EngineNut) Checked for trouble codes,base timing, fuel pressure, compression, spray pattern, etc. Checked all engine sensors as per Indmars instuctions. Condition eventually gets worse were the engine would stall and be hard to start,(engine straining to crank). Go to the local dealer while on vacation he scans the engine and finds the timing at full advance after it stalls. There way backed up with work to go any further so I'm back on the phone Indmar.They tell me it's either the ignition module or the ECM. Put in ignition module, no change. Bypass the computer so the timing is controled by the ignition module still no change. I'm pretty stumped. Engine starts and runs fine otherwise and has plenty of power. Condition will rear it's ugly head ONLY after being at operating temp. for at least 15-20 min.
Sorry for the long post guys. Any input would be really appreciated.

Buy a can of freeze mist, from Radio Shack or some other electronics supplier. This is refrigerant in a can and is used to isolate thermal issues in electronics. You won't be able to freeze individual components but you can shoot it on different areas of the heat sink (the fins on the ECM), connectors and sensors.

With no RPM info, I'm not sure seeing max advance after the motor dies is an issue- have you looked at total advance before it dies with the engine off, and are you monitoring the advance while the motor is running?

Did you check all grounds and inspect the pins of the receptacles on the ECM?

Watch the IAC when it starts to act up. If you can start it by cracking the throttle, this may be your area of concern.

[Bouyhead]

Thanks Jim. I previously had made a custom block of ice for the heat sink with no luck but will try the freeze mist so i can get to the connecters etc.

The "professional" scan i paid for while away was done with a laptop and was a little rushed do to the fact they were swamped with work. To look at total advance or to monitor advance while running you mean with a scan tool no?

I'm limited on my end here, i can read a ohm meter & a timing light but don't have access to a scan tool. Should i give my marina some action and pay for a more detailed scan? It's a big place, over 300 boats.

The only way to start the boat after stalling is to open the throttle completely. I have even pulled a couple plugs after stalling and they were dry. Do you think i should still look into the IAC? Thanks for all your input.

[JimN]

Thanks Jim. I previously had made a custom block of ice for the heat sink with no luck but will try the freeze mist so i can get to the connecters etc.

The "professional" scan i paid for while away was done with a laptop and was a little rushed do to the fact they were swamped with work. To look at total advance or to monitor advance while running you mean with a scan tool no?

I'm limited on my end here, i can read a ohm meter & a timing light but don't have access to a scan tool. Should i give my marina some action and pay for a more detailed scan? It's a big place, over 300 boats.

The only way to start the boat after stalling is to open the throttle completely. I have even pulled a couple plugs after stalling and they were dry. Do you think i should still look into the IAC? Thanks for all your input.

If someone hooked it up to the computer to collect data and charged you, they should have taken whatever time was necessary. Charging someone and rushing because they're busy is BS. If they're busy, they should work late, start earlier or hire more people- it's part of the business and nobody's boat is more important than anyone else's.

I don't know of a scan tool that will show data. If you went to the marina before, I would work out some kind of deal if they rushed you before. If they connect it to their diagnostic computer, they should be able to manually adjust the IAC with that and if it doesn't respond, they'll see it.

I can't know what is causing t his but I wouldn't necessarily remove the IC module from the list of things to check just because it was already replaced.

[Bouyhead]

If someone hooked it up to the computer to collect data and charged you, they should have taken whatever time was necessary. Charging someone and rushing because they're busy is BS. If they're busy, they should work late, start earlier or hire more people- it's part of the business and nobody's boat is more important than anyone else's.

I don't know of a scan tool that will show data. If you went to the marina before, I would work out some kind of deal if they rushed you before. If they connect it to their diagnostic computer, they should be able to manually adjust the IAC with that and if it doesn't respond, they'll see it.

I can't know what is causing t his but I wouldn't necessarily remove the IC module from the list of things to check just because it was already replaced.

Going back to the marina wasn't really an option since I was at the end of my vacation and it was to far away. I'm back home and turned over the job to my marina. They have been going over all the basics and so far nothing is jumping out at them. My last call to Indmar I was informed they don't make the MEFI 1 ECM anymore. If it is determined my ECM is bad what are my options? Can a bad ECM be fixed? Can i upgrade to MEFI 2 or 3 ? At this point I'm thinking going Carburetor or taking up needlepoint! Thanks for all the help.

[JimN]

Going back to the marina wasn't really an option since I was at the end of my vacation and it was to far away. I'm back home and turned over the job to my marina. They have been going over all the basics and so far nothing is jumping out at them. My last call to Indmar I was informed they don't make the MEFI 1 ECM anymore. If it is determined my ECM is bad what are my options? Can a bad ECM be fixed? Can i upgrade to MEFI 2 or 3 ? At this point I'm thinking going Carburetor or taking up needlepoint! Thanks for all the help.

I would call Indmar again and ask if the MEFI II is a direct plug-in. I know the knock sensor module went away when they changed versions but I don't remember which. IIRC, when they went from MEFI II to CEFI III, the relay triggers changed from positive to negative, although converting those would be easy. Eliminating the knock sensor module would be easy, too. AFAIK, they can't be opened and repaired because they're waterproof and sealed.

Have someone at Indmar compare the pinout of yours with the earliest available ECM and advise on the easiest way to make it work. Otherwise, check with boat salvage companies. If you find one, it will need to be recalibrated. FYI- Mercruiser and used MEFI controllers until '98 or '99 and Volvo-Penta used them longer.

[MYMC]

I would call Indmar again and ask if the MEFI II is a direct plug-in. I know the knock sensor module went away when they changed versions but I don't remember which. IIRC, when they went from MEFI II to CEFI III, the relay triggers changed from positive to negative, although converting those would be easy. Eliminating the knock sensor module would be easy, too. AFAIK, they can't be opened and repaired because they're waterproof and sealed.

Have someone at Indmar compare the pinout of yours with the earliest available ECM and advise on the easiest way to make it work. Otherwise, check with boat salvage companies. If you find one, it will need to be recalibrated. FYI- Mercruiser and used MEFI controllers until '98 or '99 and Volvo-Penta used them longer.

Or have these guys fix it: http://www.ecu-car-repair.com/
Quicker and cheaper...

[JimN]

Or have these guys fix it: http://www.ecu-car-repair.com/
Quicker and cheaper...

They do marine? Looked like only car.

[MYMC]

They do marine? Looked like only car.

They cannot download the marine programming (read Indmar) but that can be done by any MC dealer once he has a viable ECU again.

[Bouyhead]

I would call Indmar again and ask if the MEFI II is a direct plug-in. I know the knock sensor module went away when they changed versions but I don't remember which. IIRC, when they went from MEFI II to CEFI III, the relay triggers changed from positive to negative, although converting those would be easy. Eliminating the knock sensor module would be easy, too. AFAIK, they can't be opened and repaired because they're waterproof and sealed.

Have someone at Indmar compare the pinout of yours with the earliest available ECM and advise on the easiest way to make it work. Otherwise, check with boat salvage companies. If you find one, it will need to be recalibrated. FYI- Mercruiser and used MEFI controllers until '98 or '99 and Volvo-Penta used them longer.

Spoke to Larry at Indmar he tells me MEFI 1 or 2 will work but MEFI 3 is a different animal.
No MEFI 1 or 2's at Indmar but he did inform me the MEFI's where used by Indmar,Mercruiser, and Volvo Penta. If i located one from another manufacturer it would have to be recalibrated. What are your views on all of these automotive companys that claim to sell reman. ECM's? I questioned using an ECM from a auto application and he said the pinouts wouldn't even be remotely close. Seems like uncharted territory to me.

[btriantos]

I did not read everyones replys here, sorry. Have you checked your temp sensor? You are describing exactly what my truck's engine experienced a couple of months ago. The temp sensor was sending fast erroneous data to the computer, and it didn't know whether to S%^& or go blind. It could not keep the engine running smooth as a result. Changed it, and boom, problem solved. $20.00

[MYMC]

Another source that maybe able to help: http://www.azspeed-marine.com/mapepa.html

Not sure why you would be told that about pin outs...here is a pic compare it to what you have:

[Bouyhead]

Another source that maybe able to help: http://www.azspeed-marine.com/mapepa.html

Not sure why you would be told that about pin outs...here is a pic compare it to what you have:

Thanks for the info. Spoke to Jim at azspeed, he can set up a new MEFI 2 for $700. Seems like a pretty good price for a new not remanufactured unit.

[Bouyhead]

I did not read everyones replys here, sorry. Have you checked your temp sensor? You are describing exactly what my truck's engine experienced a couple of months ago. The temp sensor was sending fast erroneous data to the computer, and it didn't know whether to S%^& or go blind. It could not keep the engine running smooth as a result. Changed it, and boom, problem solved. $20.00

Unfortunately I went boom a few times and not just for the temp sensor. The guys on here walked me through a lot of diagnostic procedures and now my marina is looking into the problem. Just prepping myself for an ECM purchase.

[MYMC]

Thanks for the info. Spoke to Jim at azspeed, he can set up a new MEFI 2 for $700. Seems like a pretty good price for a new not remanufactured unit.

Jim is a great guy...if you only knew how long I have know them out there you'd really know how old I am!