2002 SANTE in Limp mode

[Engelwood39]

I have a 2002 Super Air Nautique with a PCM Excalibur 330.

It recently took on water from a ballast fitting failure and the water was up to the bottom of the alternator. Everything was dried out and transmission fluid looked water free, but was changed for precaution. Walters V-Drive fluid looked good and engine oil looked good.

This last weekend (about 3 weeks after we took on the water and first time out since the then) we had it out. It ran great for about 3 hours both wakeboarding and surfing. We then took a swim break at a sandy beach for about an hour.

After we left the beach the check engine light came on and it went into limp mode right away, it wouldn't go over 8 or 9 miles per hour and around 2800 RPM. Engine temp was 175 , which is where it always runs and oil pressure was around 40 which is also pretty normal I think. Tested fuel pressure and it is around 42 PSI

Anyone have an idea of what I need to take a look at to start troubleshooting and eliminating possibilities?

Thank you,

(Top of engine with cover off)


(Starboard side on engine, shows alternator for reference of how high water got)

[mpost]

The following is from the PCM manual for your engine. Normally there are separate senders/switches for oil and water temp for the gauges and the ECM. Your gauges read ok, but the ECM is putting it in PRM. You can try removing the leads from the senders and see if the problem goes away. Maybe moisture or corrosion on a connector is cusing issues.

"POWER REDUCTION MODE The ECM monitors engine oil pressure and engine coolant temperature whenever the engine is running. If either one of these inputs indicate an abnormal reading, the system will go into “Power Reduction” mode, followed by the illumination of an indicator lamp and/or sounding of the warning buzzer (if equipped). This is a feature that will help protect the engine during an overtemp or low oil pressure condition. When in “Power Reduction” mode, the ECM will allow normal engine performance up to 2500 RPM. Above 2500 RPM, the ECM allows fuel delivery through only half of the fuel injectors. Once the RPM is brought down below 1200 RPM, normal engine operation is restored until the RPM exceeds 2500 RPM. The feature allows maneuverability of the boat while removing the possibility of high engine speed operation until the problem is corrected. NOTICE: If it is not possible to safely shut off the engine, return the engine to idle speed. Once returned to idle, the ECM will allow the engine to operate normally below 2500 RPM."

[BB3557]

Same thing happen to my 2007 SANTE 220 with a ZR6, this weekend.
After pulling the kids on the tube, the warning alarm starting sounding and giving the message "Power Reduction Active - See Dealer".
Tried to do some searching on what could be the cause. I saw 3 possible causes.

1. Overheating.
2. Oil Sensor.
3. Too much water in the bilge.

I found the third one kind of odd, since there was no water in there.
But then it click in my head, that we got caught out on the water in a sudden thunderstorm/lighting storm last weekend and left her tied to the dock as we ran for cover.
It took the pumps 20min to drain all the rain water out of it when we got it home. I wonder if the oil sensor was under water and that might be cause of my issue.

[Engelwood39]

Thanks mpost and BB3557 for your responses.

The oil sensor was very possibly under water or at least getting water splashed on it. This is evident from the picture I will attach below. The Water temp is on the top front of engine (towards back of the boat) so I doubt it got wet. the oil sensor is on the back bottom of the engine on the starboard side. I can unhook it and give it a try. Here are pics to verify that I am looking at the right sensors.

Are both these sensors open ground that ground out when there is an issue? Just want to confirm that unhooking the single wire and leaving it touching nothing is the proper test for checking on a possible bad sensor.

The lake is about an hour away... If I unhook it and run it on shore with water connected will it still go into limp mode if I try to bring the engine RPM up with the prop disengaged?

[Engelwood39]

Does anyone happen to know if it will remain in limp mode if i run it on land with a hose hooked up to it? I was planning increase the RPM's willwith the prop disengaged, will the limp mode kick in with the prop and transmission disengaged?

[mpost]

The oil pressure Switch is the small one on the right side of the picture and should be shorted to ground when the engine is not running (or oil pressure is below 5 lbs). the temp sender you took the picture of I believe is for your temp gauge. This runs on different Ohms depending on temp. You should be able to verify this by grounding the wire from this sender and the gauge should spike to high temp with the key on. I suspect this is ok since your gauge was reading OK when the problem occurred.
I am not sure if this year engine uses ECT sender for the PRM mode or not. The manual does not really say.

[Engelwood39]

Ok, started it on shore and ran it for a while. IT WAS NOT AT THIS SPEED, IT DOUNDS NORMAL (AROUND 700-800 RPM) No check engine light or limp mode but rpm read on gauge at 2300-3100 RPM while idling. This was probably the case when we limped it home at the lake the other day.

[jkallen21]

Any chance you sucked up sand from the beach?
On the wiring, you may have a separate wire for the switch (activates alarm which controls the check engine light) and the sender (controls gauges). If you touch the sender to ground, the oil gauges will register full. Not sure on the switch.

[mpost]

Ok, started it on shore and ran it for a while. IT WAS NOT AT THIS SPEED, IT DOUNDS NORMAL (AROUND 700-800 RPM) No check engine light or limp mode but rpm read on gauge at 2300-3100 RPM while idling. This was probably the case when we limped it home at the lake the other day.

Do you have a display or other indication of limp mode other than the Check engine light? Was the CEL on the whole time you were returning from the beach. Not sure about your tach but my 98 has a selector switch on the back of the tach for different number of cylinders on engines. Have had erratic tach at times and rotating this selector seems to clean up the contacts and it works ok for a year two.

[Engelwood39]

Any chance you sucked up sand from the beach?
On the wiring, you may have a separate wire for the switch (activates alarm which controls the check engine light) and the sender (controls gauges). If you touch the sender to ground, the oil gauges will register full. Not sure on the switch.

I do not believe it pulled in any sand as I anchor out a ways and I didn't see any in the strainer.

[Engelwood39]

Do you have a display or other indication of limp mode other than the Check engine light? Was the CEL on the whole time you were returning from the beach. Not sure about your tach but my 98 has a selector switch on the back of the tach for different number of cylinders on engines. Have had erratic tach at times and rotating this selector seems to clean up the contacts and it works ok for a year two.

No, the only indicator was the check engine light and the engine cutting when it was around 3000 RPM. I will try to take a tach out and look at it.

[Engelwood39]

UPDATE.

Was out of town for a holiday lake trip. We took the boat and it seemed to run without issue.

Here is where it was left off at:

• left beach and putted home in limp mode RPM reading seemed higher that it sounded.
• tested at home hooked to a hose. The idle RPM read between 2300-3000 RPM but sounded normal. I disengaged the prop and revved the engine momentarily. Check engine light flashed and went immediately off, then Tach RPM dropped to normal. engine sounded the same as when it was reading between 2300-3000 RPM.
• took to the lake right after shore text. Boat ran fine.
• Took to the lake over weekend and boat ran great.

I have no idea what causes the erratic Tach reading, but I think that may have been the trigger for the "Limp mode." My only guess is that it was reading much higher than the actual RPM and when we went to accelerate leaving the beach the RPM reading jumped high enough that the boat entered some type of high rev protection mode that activated the "limp mode."

Any one have a weigh in here? Thanks for the help.