2014 Yamaha EFI gas in oil

[scooter727]

I have a 2014 Yamaha EFI golf cart, 207 hours, that runs, but it has gas in the oil. Exhaust is smoking some. I see gas oil in the air filter box side that is open, not on the filter side. I've changed the oil. The spark plug had some oil on it. The valves were checked and are in specs .004" Could it be the vacuum lines? Fuel injector open? What about the pressure sensor? Can the pressure sensor be tested? Any other possibilities? If it is the fuel injector, what is the part number and where do I get one? Help is certainly appreciated.

[scooter727]

I'm testing the fuel pressure sensor today. I guess my viewers can tag along.

[scooter727]

Fuel Pressure switch tested good. Constant red wire KOEO 5.1V, Signal wire 3.1-3.4V, tested ground 12.6 V. Tested fuel injector wire harness with a test lamp, found positive side and tested ground side and test lamp was pulsing with engine running. Next, pulled fuel injector. There is a small cut on o-ring.
Need to replace the o-ring. Ran some carb cleaner thru fuel injector. The fuel injector was NOT stuck open.

I do have a question: Is it common when running the golf cart and I get off the accelerator and stop that the fuel pump continues to run for maybe two or three seconds? I do think that this still wouldn't be pulsing fuel thru the fuel injector because I didn't see the pulsing when I tested the fuel injector; the fuel injector only pulsed when I was on the accelerator running the engine.

I'm still not sure how gas is getting into the crankcase. Anyone want to chime in?

I guess I should do a compression test, and see how good the rings are.

[rstacy]

I have run in to this a couple of times.
I doubt that it is a ring issue.
A leaky fuel injector or defective MAP sensor will do it.
I have heard of the negative side wire of the injector going to the ECU rubbing on the frame and intermittently grounding out causing the injector operation to become erratic.
The injector part number is JC0-13770-00-00.

[scooter727]

Thanks for responding. I just did the compression check, and it surprised me being on the upper range but you are right, it cant be the rings, as the compression reading was 125 psi.

[scooter727]

Originally Posted by rstacy

I have run in to this a couple of times.
I doubt that it is a ring issue.
A leaky fuel injector or defective MAP sensor will do it.
I have heard of the negative side wire of the injector going to the ECU rubbing on the frame and intermittently grounding out causing the injector operation to become erratic.
The injector part number is JC0-13770-00-00.

I'll trace the injector wires, that's a good idea!!! Thanks!

[scooter727]

Originally Posted by rstacy

I have run in to this a couple of times.
I doubt that it is a ring issue.
A leaky fuel injector or defective MAP sensor will do it.
I have heard of the negative side wire of the injector going to the ECU rubbing on the frame and intermittently grounding out causing the injector operation to become erratic.
The injector part number is JC0-13770-00-00.

The injector wires are all good; either in electrical tape or loom. Is the MAP sensor the same as what I was calling the fuel pressure sensor. My service manual calls it a pressure sensor. If the MAP sensor is different than the pressure sensor, where is it?

I guess I'm ready to start throwing parts at it; a new injector and sensor.
Thanks for your help!

[rstacy]

My bad. They are the same thing.
I had a fuel injected Adventurer that would only do this once during the winter season. Come to think of it, I should be getting that call soon.

[scooter727]

Update: I used a fuel injector pulse tester on continuous mode to test the fuel injector. I did see just a small amount of carb cleaner hanging on the tip of the fuel injector. The spray pattern was good. However, over time, this small amount will accumulate and work it's way into the crankcase, i.e., gas in the oil. Then, I decided, to do a good cleaning of the fuel injector, using the tester on continuous mode pulsing the fuel injector in carb cleaner fluid, while at the same time having the fuel injector go thru an 8 minute bath using a ultrasonic cleaner. I disassembled the fuel injector assembly, and removed the 2 o-rings. See the pictures attached. The fuel injector is in a small mason jar bathing, pulsing thru it carb cleaner. Outside the mason jar is water in the rest of the ultrasonic cleaner. No need to fill up the whole ultrasonic unit in carb cleaner.

[ThreeCW]

Here is another BGW member with a similar problem. You might gain some insight from this thread:

https://www.buggiesgonewild.com/showthread.php?t=182841