Rough Start/No Idle/Backfiring

[IslandPhazer]

After replacing the stator in my phazer, I now have an issue with it either starting for all of one - two seconds and then dying or starting and running like its on one cylinder. I've gotten a few Code 30's (Low oil pressure) but I feel like it might be a false positive just because the engine isn't running correctly and not allowing the oil pump to build enough pressure. I can make it run for longer if I slightly crack the throttle open. (Though its really rough)

I've checked the trigger coil (3V when turning over), Reseated the TB, checked fuel pressure, tested and cleaned injectors, replaced plugs and tested spark... Everything seems to check out.

Now, There is one thing that is out of the ordinary, we had to use a RX-1 Oil filter on it as We didn't have any for the 500 in stock, The filter screwed on fine and seals, but its a bit taller than the original, I would assume due to the RX-1 flowing more Oil.

Could it be possible that there is a purposely built restriction in the 500's oil filter to help it build Oil pressure? Is my oil pressure switch "Flapping" On-Off-On-Off? I feel like it has to be something strange seeing how it ran fine before the stator was replaced, just didn't charge.

Let me know what you guys think, Thanks in advance

 

[Mooseman]

I doubt the oil filter has anything to do with it. If anything, it will just have more capacity. Must have been a tight fit though.

Like you said, I also think the oil pressure thing is probably due to the low idle speed but it's possible the pump lost its prime. As far as I know, these engines are self priming and blipping the throttle gets it going again.
https://ty4stroke.com/threads/oil-pump.106114/

This thread also has priming tips:
https://ty4stroke.com/threads/op-lo-after-a-tip-over.134975/

 

[livewire_101proof]

Oil filter should be fine, I use the longer apex ones on my nytro, and also have a stock nytro one on the Phazer right now with no problems. It's not quite as long as the 4 cylinder ones but still quite a bit longer than the original Phazer filter.

After this season I planned on using the longer one on it also just so I can have a few of the same filter on the shelf that fit any of my sleds

 

[IslandPhazer]

So we tried checking that bolt for a good oil prime, no issues there, tons of oil came out when cranking

Pulled the plugs and they are wet though... seems to be over fueling for some reason, I tested all the sensors in diag mode and everything checks out from what I can see

This one really has me stumped, literally nothing has changed except the stator and that filter

 

[Voda2000]

How old is the fuel?

 

[IslandPhazer]

How old is the fuel?

Fresh, there was old fuel in it but we pumped it out and flushed out the old stuff out of the fuel rail by pulling the return line, also tested the fresh fuel for water using a testing paste, all good.

Spent another day on this damn thing. Checked timing, checked decomp on the cams, every sensor again... I'm leaning towards the ECU now just because it's the one variable that I can't test and the one thing I can't control...

 

[Mooseman]

That would be an expensive part to shotgun. Did you check the cam chain and timing? What about compression?

 

[IslandPhazer]

That would be an expensive part to shotgun. Did you check the cam chain and timing? What about compression?

Cam Chain was good and tight, All of the timing marks lined up (Cyl 1 at TDC, Flywheel lined up perfect with its corresponding mark) Compression was at 125 PSI without oil in the cyl, Haven't tested it with oil yet though.

How do these sleds usually run? The original plugs were quite black, not what I would expect from something that has EFI, the inside of the cylinders also have a pretty heavy amount of carbon for a 4 stroke.

When I can get it to somewhat run, It seems to want to run a bit better when its warmed up, Still nowhere near what it should be/was though. Backfires heavily through the Intake.

 

[IslandPhazer]

I now seem to have a code 26 that isn't intermittent, It always is on and won't clear. I've checked the sensor value in the Diag mode and it starts at 100 and very quickly drops 20 or so when cranking (Goes to 80 or 90, flashes quickly on screen)
There isn't a defined value it should be at in the service manual, and it states that the engine should still run with a faulted Intake air pressure sensor.

This sled is kicking my #*$&@

 

[Mooseman]

Maybe the hose is cracked somewhere or the sensor is bad. I remember when I'd forget to reconnect those hoses and it would run like crap.

 

[IslandPhazer]

Does this ignition timing seem strange to anyone else? Seems like the right spark fires erratically: https://photos.app.goo.gl/PKD8syd7cZ8iRuF42

 

[Mooseman]

I thought they both fired at the same time or at least completely opposite ?

 

[98SRX00]

TORS- Throttle cable too tight??
Had mine run the same way a couple weeks ago. It would flash a code but almost too fast to read it. I had put my windshield on and had routed the throttle cable in a bad spot....

 

[IslandPhazer]

Luckily figured it out thanks to Gone Blue, The stator assembly I installed from Royal Distributing (Likely a Kimpex or SPI Part) includes the Crankshaft position sensor. The terminals were wired the wrong way. Pulled the two pins out and flipped them around and up it came. There must be some kind of polarity to that sensor and the ECU was getting a weird signal without throwing a code for it.

Anyway, I hope this helps someone in the future, never trusting a Kimpex part again!

 

[Dave hache]

Luckily figured it out thanks to Gone Blue, The stator assembly I installed from Royal Distributing (Likely a Kimpex or SPI Part) includes the Crankshaft position sensor. The terminals were wired the wrong way. Pulled the two pins out and flipped them around and up it came. There must be some kind of polarity to that sensor and the ECU was getting a weird signal without throwing a code for it.

Anyway, I hope this helps someone in the future, never trusting a Kimpex part again!

#*$&@ this is exactly what money was doing but burned up stator in process same stator u said