GTX 155 Exhaust gas temp sensor code

[Britpilot]

Ski is a 2010 GTX 155. Diagnostic code is PO546 Exhaust gas temperature sensor. Ski just died and my diagnostic software pulled up this code. I erased the code and tried the ski again on the water. It started and idled ok but would not produce any thrust. Ran the diagnostics again and the PO546 code was back.
I am going to change the EGT sensor but wondered if anything else can cause this code. Is the code saying the sensor is bad or that the EGT was high? High EGT can only be caused by lack of cooling water? I am checking out all raw water cooling lines. This ski has IBR and variable trim and I notice the raw cooling water goes in and out of a fitting on the IBR actuator unit any body tell me why?

 

[red2blue]

Ski is a 2010 GTX 155. Diagnostic code is PO546 Exhaust gas temperature sensor. Ski just died and my diagnostic software pulled up this code. I erased the code and tried the ski again on the water. It started and idled ok but would not produce any thrust. Ran the diagnostics again and the PO546 code was back.
I am going to change the EGT sensor but wondered if anything else can cause this code. Is the code saying the sensor is bad or that the EGT was high? High EGT can only be caused by lack of cooling water? I am checking out all raw water cooling lines. This ski has IBR and variable trim and I notice the raw cooling water goes in and out of a fitting on the IBR actuator unit any body tell me why?

Dunno about the IBR. Check the flow of water from pump to J-pipe. On the lift remove hose from exhaust...blow on it. Replace and go for a spin. If that don't work check to see that the 3 pisser holes in the end of the J (the end in the water box) are clear and that they arent being clamped off.

 

[ski-d00]

the iBR unit is water cooled

 

[red2blue]

the iBR unit is water cooled

What kinda heat does the iBR unit put out that it requires it to be water cooled?

I can understand it requiring water pressure for moving parts to function...but cooling?

 

[ski-d00]

it doesn't generate much heat, but it sits right next to the exhaust and waterbox which get pretty hot which isn't good for a pc board to live in so why not water cool it when the cooling line is literally inches away. one problem solved but unfortunately in the first couple years there were issues of it leaking water into the pc board, new problem caused.

the moving parts are driven by it's own motor, no need for water pressure.

 

[red2blue]

Gotcha, makes sense. Not for cooling itself but protection from a neighboring heat source.

I thought it had servos but the only thing I thought of was maybe a valve allowing it to operate like opas.

Learn something new every day. Thanks

 

[3ftDeep]

May be a problem with the exhaust, not the sensor. Before replacing the sensor, I'd make sure the water lines to the exhaust are connected, and water is flowing through the exhaust so they're getting the proper cooling. Make sure your flushing connector is off. Good luck.

 

[Britpilot]

Well this one ended up being a wild goose chase! I replaced the EGT sensor checked all the exhaust water cooling hoses and even looked inside the muffler. No problems anywhere. Ran the ski out of the water checked the IBR gate was working correctly. Put the ski in the water started it and zero thrust! Nothing! It just sat there and made lots of exhaust bubbles. Pulled the ski out of the water laid underneath it and checked for obstructions in the jet intake , there were none. Tried moving the impeller with a long screwdriver it turned without turning the engine! Darn! The owner told me he thought he had run over something. He had! Something big enough to get sucked up the intake and momentarily stop the impeller. Although there is no obvious sign of damage to the impeller and driveshaft something in the driveline has sheared. So the engine is not turning the impeller, so no thrust, which equals no exhaust cooling water, hence the EGT overheat code! Looks like I'm pulling the pump apart next week. Any idea what has sheared guys? What breaks first in the driveline?

 

[Britpilot]

One more question. I noticed that when checking all the exhaust cooling water hoses that the flushing hose that goes to the bottom rear of the exhaust manifold has no non-return valve of any sorts in it. So when the ski motor is running water is being blown out of the flushing connector port on the transom of the ski? I've never looked to check this.

 

[3ftDeep]

Sounds like the splines on your driveshaft have sheared off. Pull the pump first and check at that end. Good luck!

 

[gcooke3874]

Dunno about the IBR. Check the flow of water from pump to J-pipe. On the lift remove hose from exhaust...blow on it. Replace and go for a spin. If that don't work check to see that the 3 pisser holes in the end of the J (the end in the water box) are clear and that they arent being clamped off.

Are the 3 pisser holes the "water packet holes" in this picture?