496MAG to codes, but wont run W/O
#11
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Joined: Dec 2008
Posts: 141
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From: ft lauderdale, florida
just as a side note, your digital volt meter may read a bit off from another one like it....so youy kind of have to use your jugdement on this. the injector should read approx 15.6 ohms (dependining on the meter used) anything +/_ .5 ohms means it is going bad.
#12
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Joined: Jul 2008
Posts: 248
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From: Crystal Lake, IL
Almost same problem I had this year...boat ran rough, RPMs capped and down on power...crawled around engine to find #8 plug wire in the bilge. I kept looking at this as the source of the problem, turned out to be an IAC failure. Not sure if the plug wire being off caused undue problems for the IAC, but a simple replace and all is good again. Thread located here: http://www.offshoreonly.com/forums/g...ing-rough.html
#14
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Joined: Jul 2008
Posts: 248
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From: Crystal Lake, IL
Not at first. There where codes saved, but nothing that pointed to the IAC. So we cleared the codes and I went back out on the water; it wasn't until the second time I brought it in that a single code was saved indicating a problem. If it wasn't for the hard guardian mode after a rapid removal of throttle, I'm not sure I would have known which motor or that there was a problem other than the loss of 6 mph from my top end.
#15
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Joined: Jul 2011
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Just an update to this forum. The motor has been fixed. I took it out on the water with a computer hooked up to it and the tech couldn't see anything. Sent all 8 injectors out to be cleaned and found out all of them were clogged to some degree. The dealer said that there was some bad gas going around the area and that he was having to do this to a lot of boats. Thanks for all the advice to those who replied.
#16
I believe it....I've pulled mine on two occasions since new after finding on the first go around (while hunting down would eventually be a boost pump issue) that each injector had a very fine sandy brown or rust colored grit. I pop one at a time and tap it against the fuel rail to clear it, then pop it back into place reinstalling the individual clips. Not sure if the grit comes from the tank or is an effect of Ethanol on the fuel rail/system, but it definitely is something to check on these motors and reasonbly easy to do yourself when encountering a no-alarm grimlin issue like this.



