6.2 mpi sputters between 1000-2500 rpm

[glen959]

Just got my 2005 27'SLX in the water. She starts up fine, idles nicely, and at WOT runs smooth. But on take off, she sputters a few times until the RPM's get over 3000.

Replaced the plugs/wires/cap&rotor
Replaced fuel filter
Replaced pcv valve

Idle does seem a little low...idling around 550-600 RPM

Not sure if I'm missing anything. I put injector cleaner in the fuel tank. Also had 1/4 tank from last year, put about 1/2 a tank fresh gas in it. Think it could be bad gas from last year? Or from the injector cleaner?

Any ideas are much appreciated.

Glen

 

[BonBini]

Sounds like you may have a dead cylinder that comes back in on the upper rpms.

Pull the filter back off and analyze the fuel in it.

Then revisit the “Replaced the plugs/wires/cap&rotor” job. Be sure the firing order is correct. Pull the plugs and look for a plug not the same as the rest. Take a compression test just for reference.

If you don’t find water in the fuel or a bad hole, dump alot of injector cleaner in the fuel filter and let it run for a 1/2 minute then shut it off. See how it runs after a day or two of sitting.

 

[glen959]

Thanx for the help. Checked everything again. All looks good. Going to try compression test and check all the plugs. Also thinking it may be the injectors? Not sure though

Thanks again for the input

 

[BonBini]

What hp is the 6.2, what drive, and how well does it move the boat?

 

[glen959]

It is 320 hp with a bravo II drive. It moves the boat pretty well. Cruises at about 25-28 kts I think. Not fast but fine by me. If I had it to do over again probably would've got the bigger motor but at the time I didn't know any better and was like $10,000 more (if memory serves me).

Had the boat since brand new and just got rid of my 32' sun dancer. I prefer this boat

 

[Bill Z]

Had a similar situation two weeks ago with my 320. Apparently Mercruiser had a warning that the distributors were re vented to correct the problem. Don't know if this was corrected by your model year. Mine is a 2003 with 6.2's. Beware that the part cost is $800.00 each.