2003 5.7 Gi-B Engine "safe mode" issue

SpecialK · **Joined:** Mon Dec 08, 2008 1:24 pm **Posts:** 120

My 02 268 Vista has the VP 5.7 Gi-B engine that has started to engage the "safe mode" when under load at approximately 2.500 rpm. The engine is raw water cooled, has new risers & manifolds (2nd season), a new impeller this year and a new thermostat last year. Last season I had no issues with the engine at all. I have checked the oil level and it is fine. My understanding is that the ecu (engine control unit) monitors oil pressure and engine temperature and will engage the safe mode if an overheat or low oil pressure condition exists. The oil pressure and engine temp guages all read normal. In an effort to resolve the issue, I have installed new oil pressure, water temp switch and exhaust elbow temperature sensors. I continue to get the "safe mode" engine alarm when attempting to accelerate and get on plane. When I restart the engine, the alarm resets and will not sound again unless I accelerate and hit the 2,500 rpm level. I know there have been a few threads on this board about the topic, but I am looking for some guidance in troubleshooting the issue. I don't believe the engine is overheating as I can place and keep my hands on the risers when the engine is running and immediately after the alarm sounds. Any ideas as to what else might be causing this issue....fuel pump, electrical grounding issue etc. Any suggestions would be greatly appreciated. My mechanic will not be able to get to me for another 2 weeks so I would like to resolve the issue myself. Thanks in advance for the help.

captwalt · **Posted:** Thu Jun 24, 2010 10:03 am

Does EPM kick in when you begin to hit some chop?

SpecialK · **Joined:** Mon Dec 08, 2008 1:24 pm **Posts:** 120

The safe mode kicks in calm seas as well as in chop

captwalt · **Posted:** Thu Jun 24, 2010 5:59 pm

There was a post on here recently that discussed a simple solution to a similiar problem that was not related to either the oil pressure or overheating. Take a look at it and see if it is similiar to your issue viewtopic.php?f=11&t=5800 The fix is free if you know how to use a screwdriver.

KDriskel · **Posted:** Sat Jun 26, 2010 7:58 am

I had a similar problem with mine ( but only when hitting heavy chop) turned out to be a bad connector inside the lanyard kill switch.

The fault mode will mostly engage from high water temp, low oil pressure and high manifold temp and low fuel pressure, (plus apparently the kill switch...)

In your case because it is engine RPM specific, I would lean towards a bad oil pressure sensor. As the engine RPM comes up, the oil pressure does as well. 2500 RPM probably puts your motor at or near its peak pressure (60psi ish. If the sensor (not sender, that drives the gauge) wasn't reading properly, or was disconnected somehow, that would immediately put the engine into safe mode. I don't know where to find the data, but with the specs, you could probably test the sensor with a good volt meter ahead of the mechanic plugging in the computer.

Just my guess, but perhaps a starting point.

SpecialK · **Joined:** Mon Dec 08, 2008 1:24 pm **Posts:** 120

I checked the lanyard shut off switch connections as well as replacing the oil pressure and engine temp switches and still have an issue. I brought the boat to the mechanic Saturday. I hope the problem is not major and big $$$$! I also hope to be out on the water for July 4th.

captwalt · **Posted:** Mon Jun 28, 2010 3:43 pm

Good luck with your issue.... let us know how it turns out.

KDriskel · **Posted:** Tue Jun 29, 2010 9:35 pm

Good luck! I hope they get it back to you in time. Let us know how it turns out.

SpecialK · **Joined:** Mon Dec 08, 2008 1:24 pm **Posts:** 120

I finally have an answer to my ECM dilema. The mechanic was stumped by the issue and spent quite a bit of time diagnosing the problem. Turns out to be a bad MAP sensor which was causing the engine to go into safe mode. He hooked the engine to the shop computer and no error codes were reported. After some additional research and a call to VP support, the MAP sensor was replaced and the engine now runs normally. I'll have the boat back in the slip for the long Holiday weekend.

firecadet613 · **Posted:** Fri Jul 02, 2010 3:35 pm

Glad to hear it was an easy fix...and thanks for posting it so I know where to look if I have this issue in the future!

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2003 5.7 Gi-B Engine "safe mode" issue

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