Check Engine Light Question

[Patman941]

Today after cruising for about 20 minutes, check engine and overheating light for starboard engine came on. Stopped engines, checked the clean out port, nothing, and noticed both pissers were performing normal.

I went through the resetting processes, disconnected the batteries, on/off numerous times, and both error messages eventually cleared.

Began cruising again, after 10 minutes, same issues and codes. Limped back, then stopped for a while to do some swimming. Then went through the reset process, and after sometime, both codes again cleared. Cruised back to ramp, about 15 minutes, and no error codes thrown.

Got the boat on the trailer and back home. Got underneath the boat and nothing seen. Flushed both engines without issue.
This has happened once before about 9 months ago, but not since.

I’m thinking Oxygen sensor. Anyone else got any other suggestions?
Replacing the O2 sensor easy, anyone done it? Trying to figure out if I can do it myself or do I need to pay an arm and a leg to have a mechanic do it? Thanks all.
2016 242LS.

 

[Neutron]

An o2 sensor wont give you an overheat alarm.
Did you get the actual code from the connext diag screen?
Before you go replacing unnecessary parts, i would start there. If you can't get any usable info on the diagnostic screen than you will need to scan the ecu for that engine that gave you the alarm

 

[Patman941]

Connext screen no longer has any error messages. I assume the diagnostic screen won’t reveal any helpful info.
Scanning the ecu I’m sure needs to be done by someone with the appropriate software, ie not me!! Lol

 

[Cobra Jet Steering LLC]

Possibly a bad heat sensor , very common but also check the oil level

 

[robert843]

Did you actually get an alert saying over heating? One of the most common engine alarms in these boats is when a battery is failing our a battery connection is loose. The alarm makes you think you blew a motor lol but it really can be something as simple as a battery a lot of times,

 

[Patman941]

Checked the oil, which was in normal range, but a little less than the port side. So I added about a 1/3 of a quart.
I’ll get out there today with a multimeter and check the batteries.
Thanks everyone for the troubleshooting ideas. Keep ‘em coming!!

 

[HawaiiBreeze]

Yes the O2 sensor(s) are relatively easy to replace. I just did my 2nd one yesterday. 17mm open end wrench, lay across the engine and unscrew it. However you should have received a Code if it is faulty.... This code is for the O2 Sensor "after" the Cat Converter. There is also an O2 Sensor "before" the Cat Conv which is a different code. FYI the After sensor is the harder of the two take out of course.

One last comment about going into Limp Mode with no visible reason: "Negative/Grounding" A lot of people are finding out that bad grounding/wiring etc or a bad battery is the culprit for these symptoms. Battery Cables have a tendency to "look" ok but are in reality corroded inside creating a weak ground which these sophisticated engine mgmt systems interpret in strange ways.

 

[Patman941]

All great information. Thanks everyone. Do you happen to have a picture of the O2 sensor you replaced, or where exactly it was? I’m pretty sure it’s on far end of the engine (making it the most difficult to see or get to).