525 EFI alarm 2800rpms
 

Im running my '04 525 on a hose after top end refresh and am getting an audible alarm at 2800 rpms and it starts to misfire or go into guardian mode, I can't tell which is which. My gauges show at 2800 rpms water temp 165 water pressure 26psi oil temp 175 and oil pressure of 52psi. I think its a steady constant tone alarm. It runs and sounds perfectly fine up to 2800ish. Anyone else experience this or should I just go pay to have the computer scanned now? Thanks

OVERSPEED fault alarm then throwing it into Guardian mode. running PCM controller and engine unloaded / water hose and especially throttle only the overspeed fault depending on app can come in at 2500 to 3500 rpms.

Even in the water reving in the throttle only position can do the samething but happens more so on the water hose - unloaded.

Next guess is low water pressure and or its sensor possible bad or connection or wire problem to that circuit - you say 26 psi I would then question mark this as being the problem.

Next guess is crankshaft sensor problem of some sort. / crankshaft position sensor rationale.

My guess is anyone of These plus they are all steady horns and guardian is or can activate.

scan the engine before anymore running

Why are you running it at 2800 on the hose?

^^ This ^^ I would immediately change out the impeller and housing after you ran above idle on the hose with a 525 EFI. The headers are very sensitive (hairline cracks develop, welds fail) to the slightest warming from a less than 100% efficient impeller/housing. Better safe than sorry with the 525 header history. If you have to run it to high RPMs to break in your engine go to a ramp when its empty or find a tank set-up to dunk the drives in.

I should have stated its not really on a hose, the lower unit is in a tank with a hose filling it. I guess I should go get it wet and see if it happens under load then.

It will not rev over that with the drive in neutral. It's a safe guard.

If you want to rev it over 2800 rpm in neutral (which you should really have no need to do that), then you need to jump out the neutral switch on the shift quadrant.

that's the shift in gear switch to tell the PCM if the drive is in gear or neutral. really do not mess with that switch on the shift bracket - that switch when it fails or even becomes out of position can stall your boat and of course cause other problem. There is a code for that switch when it fails but believe it or not sometimes it will not show up as the problem on the scan. been there and seen that one. .

the fault and horn is Overspeed when you scan it will show how many times as well.

Sounds good guys, done revving. Time to water test. Thanks again

Sounds like a neutral overspeed condition to me. I get those alarms as soon as I rev above 2300.