Re: cutting out
when was the last service on the O2 sensor,the VST filter or a test of the low pressure pumps?<br />my guess is its running out of fuel. ya need to fix it before a piston pops, that 3.1L motor will pop one in a heartbeat if its run lean.<br /> I reccomend replacing the low pressure pumps as routine maint about every 3 years, the 3.1L motor is very hard on them. the O2 sensor needs to be cleaned AND the output tested at least once a year or every 100-200 hours depending on how its used. a dirty or defective O2 sensor can lean out the fuel mix.<br /> weak pumps can create a low fuel situation in the VST causing low rail pressure causing a lean out. a clogged VST pump filter can restrict fuel causing low rail pressure causing leanouts. leanouts destroy pistons.<br />most of this maint is easily accomplished by the average backyard man. you will need the service manual, maybe an 03 marine tech guide, a few test harness's and a DVM and a fuel pressure test guage for EFI.<br /> while it looks complicated the system will trouble shoot itself if you let it.<br />the hard part is testing for clogged injector filters.<br /> I am starting to reccomend a service of every 2 years remove the injectors for service,especially if the fuel system has been contaminated.<br /> luckily electronics failures on that motor are very rare. very expensive but very rare.<br /> also check the spark plug caps for proper resistance, a bad cap can create issues.
