merc 350 mpi sensors

[wags23]

my fuel reg went. replaced it, friend poured geen coolant into fill with the orange gooped up in the thermo housing and ran hot on the test run .cleared and flushed .ran at 165 temp but shuts down at 3000 rpms .did code test today fuel pressure sensoe and engin e temp sensor came up. can not clearing the codes cause the engine to lose some power at 3000 rpms?

 

[Don S]

Re: merc 350 mpi sensors

Huh

 

[wags23]

Re: merc 350 mpi sensors

i should read my post before sending. the question is will the codes not being cleared effect the running of the boat.

 

[Don S]

Re: merc 350 mpi sensors

Good question. Never tried fixing a problem and not clearing the codes if one was set.

 

[maxxman04]

Re: merc 350 mpi sensors

you are correct. if the ecu has sensed trouble and set codes, it will go into a default settings mode and basically run just enough to move vehicle/vessel, and will not return to normal until codes are cleared. depending on the year of boat/motor/ecu, makes a difference sometimes in how to clear codes, but usually disconnecting power, remove battery cable, for a few minutes will reset them. some systems tho need a special code scanner/reset module to reset, which is usually best to have a competent marine mechanic handle.

 

[wags23]

Re: merc 350 mpi sensors

i just learned how to check the codes with a led and a piece of wire from the guys on here.but couldnt get the boat for a test run because of the tides.

 

[maxxman04]

Re: merc 350 mpi sensors

a bit of caution tho, make sure that method will not damage the ecu. some of the newer systems can be damaged by "shadetree" methods.

 

[Fun Times]

Re: merc 350 mpi sensors

i should read my post before sending. the question is will the codes not being cleared effect the running of the boat.

No it will not effect the running of the boat by not clearing the codes. As long as the problem is gone the boat should run fine.

 

[wags23]

Re: merc 350 mpi sensors

i have the directions on how to reset the codes with led and the piece of wire. its 1999 mag 350 mpi .

 

[Don S]

Re: merc 350 mpi sensors

Why don't you give us some idea what engine, year, better yet a SN so we can give some accurate information.
350 MPI's have been out for years, not all with the same ECM and sensors.

 

[wags23]

Re: merc 350 mpi sensors

1999 350 mag mpi s/n ol340964. thanks i'm new at this .

 

[wags23]

Re: merc 350 mpi sensors

it idles good runs good up until 3000 and then loses power can it be the sensor still set on default mode?

 

[maxxman04]

Re: merc 350 mpi sensors

suggest getting a manual somehow someway, quite possibly from the "ADULTS ONLY" sticky here. look for your year, make, should be able to download for free. or order one, wait a day or two. it would save alot of headache and money to be certain of your system. in automotive, it was around 2000 ecu's changed. the old trick with the led and such will fry the system. average cost to fix: $2000. easier yet, drive boat to marine mechanic, have him verify system, maybe even read and reset codes, at a nominal cost. $100 is better than $2000.

 

[wags23]

Re: merc 350 mpi sensors

yea i would hate to burn the module . engine date late 98, but i think they go by s/n's. i wasvery careful double checking the wire colors for the ten pin when testing .I have amanual and looking to buy a ddt.

 

[Fun Times]

Re: merc 350 mpi sensors

it idles good runs good up until 3000 and then loses power can it be the sensor still set on default mode?

What dose the engine do and sound like to you when it dose it at 3000 rpms?

 

[Don S]

Re: merc 350 mpi sensors

The Mercruiser/TechMate is the best and most inexpensive way to get all the information from your ECM. Not a big screen, and takes a bit longer than the mega buck models, but it will get the job done.

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

 

[wags23]

Re: merc 350 mpi sensors

at 3000 rpms it loses power . fuels good new tank

 

[Fun Times]

Re: merc 350 mpi sensors

at 3000 rpms it loses power . fuels good new tank

Have you put a fuel pressure gauge to the fuel rail yet to see what the psi is? Did this just start to happen with the new fuel tank?

 

[wags23]

Re: merc 350 mpi sensors

fuel pressure reg went. replaced it and stopped smoking and running rich . the fuel pressure had gone up to 80 pounds. this was not long after new tank.

 

[Fun Times]

Re: merc 350 mpi sensors

fuel pressure reg went. replaced it and stopped smoking and running rich . the fuel pressure had gone up to 80 pounds. this was not long after new tank.

Have you pulled your spark plugs yet, They could be rich and holding you back on power after running 80 psi.