Oxygen sensor part number

[DaleHollar]

Advance Auto Part number 19370065
Bosch part 15727 Price 48.88

My motor is a 98 225

I was having the same trouble alot of people on here are having. Sometimes motor would run strong. Other times it would surge losing rpms and speed. I had already changed my fuel pumps out. So I eliminated that as the cause. I figured out over time is was worse when I was fishing tournaments when I really got on it out of the hole. It led me to believe I was flooding it or it wasn't getting enough fuel. My plugs were always real wet though.

The motor also had a little stumple if you eased into the gas slowly on takeoff.

I hooked a multimeter up to the o2 wires and ran motor on hose to check to see what the voltage was reading. It would read between .03 and .05 almost all the time which I had posted on here about. Note it should be reading .3 not .03.

The o2 sensor I purchased has a larger body so I left my head shield off. I changed out the O2 sensor and checked the voltage again. It would read beteen .30 and .80 and the voltage really jumped around alot like it's supposed to do.

Took boat to lake to run it. Made a huge difference, motor no longer surges at all. I still had the stumple on takeoff till my second trip but now it has gone away.

Plugs are alot dryer and tan to light brown now. I also seem to be using less fuel then before.

Hope this can help someone.

Donald

[BlackChamp]

Thanks for the information!

[MNXD9]

Awesome

[SkeeterBoy1987]

How did you get the sniffer end of the sensor to go into the motor. All the automotive ones that ive seen has a much larger sniffer end then the oem yamaha o2 sensor? Did you have to customize it somehow?

[DaleHollar]

no, i measured it to make sure it wouldn't bottom out. It fits down in the stock holder.

Donald

[SkeeterBoy1987]

i guess they must have changed it in the 2000. my o2 sensor sniffer is about 1/4 inch around and the other one is a solid 1/2 inch so it didnt have a chance to get in there.....ill have to try to figure out a diff plan or just break down and buy the yamaha one.

[DaleHollar]

The one I took out was alot smaller then the one I put back in it. Just take the housing off and goto advance auto and see if the part number I put in will fit it. Save you money if it does.

Donald