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mecury 115hp efi problem

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stroker87

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Hi every one! having some problems with my outboard on my toon looking for help

engine only has 73 hours on it was winterized by the local basspro took it out a few weeks ago for the 1st time was really hard to start and would not idle, after running it around 2k rpms for 15 to 20 minutes it would idle a little then die changed the fuel witch really did nothing ran it on the lake for about an hour total it will idle but it ruff I installed new plugs that didnt help either? when its running if i pull the plug wires off (1 at a time) cylinder 1 & 2 does not change the idle much (very little) but still runs, when I pull cylinder 3 or 4 it dies out? I thought it might be the injectors but I swapped them around didnt change any thing? I was working on it at night and noticed even though I have spark on all 4 plugs its much stronger on cylinders 3 & 4 then cylinders 1 & 2 ??? when you pull the plugs you can see plugs 1 & 2 are more black

the tech at bass pro is telling me its my thermostat engines temp is 120 degrees at idle but does climb when idle is raised, I boiled the stat and it did open so i think its working correctly

why would cylinders 1 & 2 have less spark then 3 & 4?

engine info: 115 HP model 1-115f13dd 2005 4 stroke EFI (yamaha/mercury)
 
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I boiled the stat and it did open so i think its working correctly
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That test is the same as sticking your arm out a car window to see if it is open...all you know is there is no glass! But, you don't know why.

You need to heat the Tstat in hot water until it opens up and quickly insert a string into the opening and let it cool off and close. Next bring the water temp in a pot up w/a thermometer in it and hold the Tstat in the water by the string. When it drops off the string read the water temp.

Is your engine a 4 stroke? What year and SN?
 
the engine plate says DEC 2004 its is a 4 stroke EFI Ser# 1B115522 Model 1-115F13dd

I did test it and it started to open around 140 degrees and was fully open by 180 degrees
 
That is the way my 115 HP 2 stroke runs.
when I pull cylinder 3 or 4 it dies out?
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That's verification of the mechanic's statement. You are going to have to break down and get it scanned to see what is preventing it from firing all four cylinders. A carbed engine like mine does it by not using low speed jets in two carbs. I assume the 4 stroke uses a computer to turn the injectors on/off. It may be a throttle position sensor.
 
Today I pulled the injectors and cleaned them its running better but still not 100%, I messed with the TPS sensor that helped some too

can some one tell me what the TPS sensor should read if i put a multi meter to the pink and black wires to set it correctly?
 
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