2006 Mercury four stroke stumble

"Hey guys, was wondering if an

"Hey guys, was wondering if anyone has encountered this situation. I have a 40 h.p. four stroke Merc. 2006 model year, fuel injected. It sits on a Bass Tracker pro team 170tx boat. When I go to put it on the trailer, really putting it under a load at W.O.T. there is a brief stumble. I don't think it has done this just coming out of the hole on the lake, just going back on the trailer. It's aggrivating as all get out. Don't know if it's a software issue or starving for fuel. If a car in my stall was exhibiting this symptom I would first check fuel pressure. Thank you, Jonathan Taylor"

"Jonathan, 4 stroke are still

"Jonathan, 4 stroke are still "new" to most of us here and haven't seen alot of the "quirks" yet to be able to say (that's the problem).

Your assumption about fuel pressure sounds reasonable - perhaps check out any fuel filters you have in line, the water separating filter (under the hood) - although fairly new there are the two fuel pumps which could be suspect and a fuel pressure regulator.

If you have any warranty left (should be 3 years from purchase date) I would get it in and get her hooked up to the computer - could also be a glitchy MAP of TPS.

Dang, sounds more like trouble shooting for an Indy racer than an outboard "

"Thanks Graham, I still need t

"Thanks Graham, I still need to get the manual for it. I'll check fuel filters and such. May be talk to a Merc guy(if they'll divulge any info). I'd like to figure something out, the motor otherwise runs good, quiet, good fuel economy. Just a pesky stumble. Jonathan Taylor"