Running on only one cylinder.
- Thread starter BenCrockett
- Start date
Put in a new capacitor, no better. Put in a used, supposedly good, regulator, no better. Next is pulling the engine to get to the stator...
I dont see anywhere in your posts that you have checked the compression. Verify that you have good and equal compression on both cylinders.
When the problem first began it was intermittent, the sled would run great, then momentarily run crappy, then back to good. As time passed it got worse until now, once it warms up it runs only on the one cylinder. Could this be possible with low compression in one cylinder? The intermittent way it began made me think compression wasn't an issue. I'll get a tester and check it to be sure. Thanks for the ideas, this is stumping me and I'm getting tired of throwing parts at it.
yes it can..
also, i know a chipped reed wouldnt cause it to run on one cylinder, but you may have chipped a reed, and ingested something in the motor, and damaged cylinder/rings causing the issue as well...
so in short..
--check compression, WHILE holding throttle wide open while pulling motor over, with kill switch shut OFF
--check your reeds VERY carefully for ANY chips..
report back, before you spend more money
So...compression is 110 lbs on mag side and 105 lbs on clutch side. About to pull the engine out to replace the stator. Should I warm it up and recheck the compression?
No the compression seems about normal. You may have a stator or fuel pressure issue. Have you checked the fuel pressure?
When the problem first started, I took the sled into the shop for them to run diagnostics on the computer and they also checked the fuel pressure and they reported that it was producing "good" pressure. I haven't personally checked it...
Replaced the stator this morning and inspected the reeds. I have damage on both sides. Going to see if anyone in town has new reeds...
So, if stator or reeds don't fix the problem, and I doubt they will, I'm thinking the ECU is the next step. I probably am going to look for a used unit due to the price of a new one. Does anyone know if a "red" ECU can be reflashed to a "yellow" program? I am starting to look for a used ECU and will try to get a "yellow" one as that is the color I am now, but if a "red" one could be reflashed, I have access to one now. Any input is appreciated.
Yeh you can flash them for any cold injector at the dealerships..
I also have a used ecu if u need one. (Pm me if needed)
Good luck bud.
P.s.
vf3 reeds are garbage IMO...stock are best. But u must replace throttle body boots as weakly since vf. Reeds must have modified boots to use.
vf3 reeds are garbage IMO...stock are best. But u must replace throttle body boots as weakly since vf. Reeds must have modified boots to use.
If you suspesct the ECU and have another ECU try it to see if it solves your problem. If it does then you can take it to a dealer and have it reflashed to the proper color injectors. Dont ride it with the wrong ECU Injector color.
Or if you have a quality multi-meter, locate and back probe the wires that come out of the ECM that go to the mag side injector to verify the correct resistance still and during the wiggling of the wire harness and then when engine is running to verify ECM is commanding that injector to fire. I know it's kind of difficult since you have to remove the tank but it is possible. I have had to do this on a couple of 900's (05''s)
This can be done if you don't have a spare or loaner ECM. At this time it would be a good idea to verify a good clean ground and also run an extra ground wire to the motor. A quality set of alligator clips with quality wire can be a quick way to add an engine ground.
Hopefully you have already checked the mag injector wire harness and connector closely and verifying there isn't a short to ground from a wire rubbing somewhere along that circuit. Sometimes a short to ground on a circuit like this can pop an ECM and if not located, found, and repaired can pop additional ECM's.
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Good luck
This can be done if you don't have a spare or loaner ECM. At this time it would be a good idea to verify a good clean ground and also run an extra ground wire to the motor. A quality set of alligator clips with quality wire can be a quick way to add an engine ground.
Hopefully you have already checked the mag injector wire harness and connector closely and verifying there isn't a short to ground from a wire rubbing somewhere along that circuit. Sometimes a short to ground on a circuit like this can pop an ECM and if not located, found, and repaired can pop additional ECM's.
\
Good luck
I have a "red" ECU that I am going to have the dealer reflash to the the "yellow" software and then I am going to put it all back together. The ECU I am going to reflash is used, but supposedly good. I also have put in a used, but supposedly good stator. Unfortunately this means I won't know if the stator is the problem or the ECU, but I am tired of pulling it apart. At this point I don't care what the problem is as long as this POS runs.
As a side note, I have inspected the wiring to the injectors and the wiring harness, in general, no less than ten times without finding any sort of fault.
Wow, I have never been so frustrated with a toy before. Installed and reflashed a "good" used ECU, examined the wiring, reassembled, and still the same problem. I'm going to have to try to connect my multimeter to the lead going to the mag injector and then run the engine and see if, once it gets hot, that signal changes. I'm planning on disconnecting the mag injector, connecting my multimeter to the harness coming from the ECU, reconnecting the fuel lines, and running the engine. I'll watch the meter until it gets warm enough to where it normally craps out and see if the signal changes. Is this a good idea? Any other suggestions? I'm also contemplating a new wiring harness. Can the injector bench test well and then malfunction once warm? Any help is appreciated.
Tested the fuel pressure myself, and it was about 62 psi and remained there even when the mag cylinder quits.
Anyone have a good used yellow mag injector they want to sell me? Should I try to get both injectors? I really don't want to buy new ones...over $400!
Anyone have a good used yellow mag injector they want to sell me? Should I try to get both injectors? I really don't want to buy new ones...over $400!
I dont think the reeds would cause this problem.
Mine had actualy fallen apart in the cage with a half inch gap.
It only caused low idle and a bog at part throtle. top end was fine.
Switched injector leads (top to bottom) will run good up to half throtle and give you a big bog on the top end.
Rob
Mine had actualy fallen apart in the cage with a half inch gap.
It only caused low idle and a bog at part throtle. top end was fine.
Switched injector leads (top to bottom) will run good up to half throtle and give you a big bog on the top end.
Rob
