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Jeff G.
Jeff G., Marine Mechanic
Category: Boat
Satisfied Customers: 4728
Experience:  42 years experience, Certified Master Technician, All Major Outboards, Sterndrives, Hi-Performance
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2005 150 yamaha four stroke goes into limp mode and dont know

Customer Question

2005 150 yamaha four stroke goes into limp mode and dont know why
Submitted: 2 years ago.
Category: Boat
Expert:  Jeff G. replied 2 years ago.
Welcome,this question may need more than a single answer. Please post back with additional questions on this at any time.
Do you have a gauge package on the boat?
Is the engine overheating?
Oil level low?
Are you getting any warning horn signals? Solid tone? Beeping?
When does it go into limp mode? Are you sure it is limp mode or is the engine not putting out?
How is the idle?
Customer: replied 2 years ago.
it has a bar above the temp symbol, it did not flash, does not show actual temp, same with oil pressure
oil level is good-solid tone, ran at WOT for 5 miles than RPM dropped, shut motor off waited a few minutes and ran the erst of the way at WOT with no problem another 3 miles, thermostat has been changed
Customer: replied 2 years ago.
temp bar did not flash runs fine at idle and WOT otherwise
Expert:  Jeff G. replied 2 years ago.
You may have has a intermittent glitch from either the temp or oil presser sender. Either one will sound the horn and go into limp mode. If the engine was overheating when the temperature drops below 266* then the system will revert to normal, same with the oil pressure. Unfortunately you need to duplicate the problem. Is your oil over the full mark?
You could of had a partial obstruction on the lower unit, then when you stopped it cleared itself. Seen that numerous times with ice bags in the water.
Your dealer has diagnostic software that he can put on the engine looking for trouble codes and overheat or oil pressure problems.Other than that we need to duplicate the problem and test when the problem is occurring. If the alarm sounds, check the temperature on the cylinder head, an IR thermometer is great for this. If the temp is OK then oil pressure may be the problem. Replace the oil sender with a oil pressure gauge and monitor the pressure. You may be able to rent one from your local auto parts store.
Let me know what you find and we can go from there.
Customer: replied 2 years ago.
will swap temp sender from one motor to another-have twins on the boat- and see what happens-than try oil sender
Expert:  Jeff G. replied 2 years ago.
OK, post back when you try it.