2007 Tahoe Q6 merc 5.0 305 MPI motor won't start after running it

alldodge

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ok just tried it, I let it run and warm up. killed it and tried starting , it wouldn't start. disconnected wire going to the tach, still didn't crank up

Need to find out if your getting spark, and if you are then it has to be fuel control related.

If spark is there, pour about an ounce down the throttle body
 

alldodge

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You know with getting 2 beeps there would be a code showing
 

perkins71

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I know might be a long shot, they overhauld motor and don't remember if wires went some place or not
 

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alldodge

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Holly crud Batman
What color are the wires? Look like Black, Tan and Brown
 

perkins71

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lol yes I know right, I think it is black, tan and brown. I'm not at the boat right now. ends of the wires looks like they would bolt daown
 

alldodge

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Its a maybe

Finding Tan wire for Analog Temp sender
The Brown goes to the PCM harness and it connect to the Neutral Safety switch. This is a maybe but look at the shift plate, but in most cases they use bullet connectors
Black is Ground and maybe something is not grounded correctly

Would like to spend some time trying to figure out were they went before. Merc wouldn't put tap on the connectors
 

alldodge

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when they put it on the computer they said something not grounded or unplugged

I would have to agree, need to find out what those wires went to. Look close by what is nearby that the wires can go to. Is it next to the shift plate?
 

perkins71

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no if your looking at the motor from standing in boat it's between the throttle body and lube bottle

I think it can reach the shift plate
 
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alldodge

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Wonder if those go to the Mercathode? It uses Black, Brown, Orange and Red/Purple.

So far as something not grounded, look behind the block you should have the negative battery cable, 10 AWG wire from engine harness, smaller Black going to transom assembly, and possibility another 8 or 10 AWG coming from the EFI harness
 

perkins71

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I was thinking the Mercathode, what would be the location of the mercathode assembly?

sorry I just looked up up and it said it would be behind my oil filter if I have one. is that correct, should I have one?
 
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alldodge

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I was thinking the Mercathode, what would be the location of the mercathode assembly?

sorry I just looked up up and it said it would be behind my oil filter if I have one. is that correct, should I have one?

The Mercathode can be mounted in many places, doesn't really matter so long as its connected correctly. You don't need one unless the boat is kept in the water. That said, this would not be causing your current issue.

What surprises me is you have Smartcraft but the display is not telling you anything?
 

perkins71

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all I did was read the directions and plugged it up and the Bluetooth light would just blink nothing else. I brought it back, I thought of bringing it someplace and let them install it.
I didn't get a chance to look for the Mercathode it was raining and lighting. I will check this evening.
 

perkins71

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no what I had bought was the smartcraft vessel view and I couldn't get it to work so I brought it back

I was told by one person that smartcarft would work on my boat and another person said they not sure.
 

alldodge

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OK, guess were back to looking for something not grounded or disconnected
 

perkins71

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Ok couldn't find a Mercathode on my boat. And the 3 wires is black. Brown and red. And the wires come out of the same harness as the lube oil wires
 
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