Mariner 200 EFI will not start

[Pond water]

Engine cranks and almost starts just don’t fire up
engine will run when I supply fuel with spray bottle

Boat sit couple years. Cleaned fuel system. Got priming bulb in fresh tank of fuel
removed vst and cleaned
removed regulator cleaned screen
removed high pressure pump cleaned screen
changed fuel lines
changed fuel water separator
fuel pressure is at 39 psi when electric pump cycles for 30 sec
low psi pump keeps vst full, as anytime I remove hose from vst fuel flow/psi is there
had injectors cleaned and checked by brucato

***engine will run when I supply fuel mix with spray bottle
i don’t think injectors are spraying/injecting
rail fuel pressure is good while cranking, regular pops off at around 38 psi


how do I check voltage at injector plug?
as I have battery voltage at red wire at injector plug

[Pond water]

0g131201 is serial #

[Merc 2.5]

I'm no efi guy but there are many here who r ... buttttt... sounds like comp ecu or what ever it is , driver isnt firing all injectors. Someone will respond with ur info. I have a manual. I'll look see if I can locate sumthin.
Welcome s&f

[Pond water]

Merc
i have a Manual, but maybe I’m missing something.
but I can’t find how to check injector harness with a
engine not running. I guess I need check voltage at plug
while cranking

[Merc 2.5]

I wish I had more info to help ya but I dont , I just fool with carby, u should have trouble shoot in fuel part manual and how to test

[Tritontr19]

Seems I recall reading kill switch interrupts injectors circuit.
i do have a Merc ecm for that engine. Clay

[RSWORDS]

0g131201 is serial #

Someone has been on BBC

Get a node light and check if the injectors are firing

[Pond water]

Ok guys I can spray some mix in air
box. Crank and it will start and idle fine now.

but it want start on it’s own. I checked
compression on all cylinders and all around 120psi

[TEXAS20225]

i just had one doing the same thing guy brought it from another shop they blamed injectors, after checkin everything turn out to be bad injector harness in side plemun

[Whaaaaat]

Injectors were recently cleaned, or before it sat for 2 years? If they sat unused that long they are probably gummed up.

[Motv18]

What is cranking voltage most merc computers need 9.6 to even turn on. So even with enough to spin the pc will shutdown.

I always start with batteries on no starts.

[Pond water]

Injectors have been cleaned/test this week. New battery with 14 volts
Engine cranks no start. I spray a little mix in
intake and it will then start and idle

[Tritontr19]

Temp sensor with 3 wires on cyl head tells ecu when
to run rich for cold engine. Maybe it’s saying its at operating temp
and is too lean for starting.

[Pond water]

Triton
I disconnected both tan/black stripe wires from
temp sensor. Engine fires right up every time.
Looking at troubleshooting that sensor now

[Tritontr19]

With it disconnected it should run about 40% richer than normal.
Those sensors are not very expensive, replaced mine last year.