ECU is it bad, don't know

[PNW Rook]

- How can you tell your ECU is the issue?
- Is there testing that can be done without a DW?

I'm working with a 2008 700 Dragon, it runs fantastic, sounds strong. My issue is high idle, 3200rpm's yeah kind of a lot.

What have I done to remedy?

- cleaned throttle body
- replaced throttle body boots
- cleaned reeds
- cleaned and rebuilt exhaust valves
- replaced o-rings on injectors
- sensors tested
- coolant
- air intake
- exhaust
- TPS
- reset the TPS .7 base, .95 idle
- throttle cable slack
- brake clean test for vacuum leaks

I'm leaning towards the ECU, no?
Is it possible that it's reading the sensors incorrectly.

 

[Polaridice]

Dont let the smoke out bud! I would get it checked out before you run it any more, Yes Digital wrench will show you your voltages at multiple places, inj, chassis, system, charge, etc whatever they are called I cant recall exactly. But I think its got something to do with your grounds or maybe lack there of. especually from the stator to reg/rec. The ecus are wired directly to the stator on pretty much every polaris sled and that can get expensive when things go wrong. So on the 700 dragon in 08 thats a touchy era depending on your electrical system I would not go swapping anything electrical unless you are certan its for your vin, year, make model part number tripple make sure for sure! On another theory you could have a crancase leak because its possible the engine may not respond like you would think using the starting fluid vacuum leat trick. At least I wouldnt rule that idea out without knowing for myself is all im saying.

 

[PNW Rook]

Dont let the smoke out bud! I would get it checked out before you run it any more, Yes Digital wrench will show you your voltages at multiple places, inj, chassis, system, charge, etc whatever they are called I cant recall exactly. But I think its got something to do with your grounds or maybe lack there of. especually from the stator to reg/rec. The ecus are wired directly to the stator on pretty much every polaris sled and that can get expensive when things go wrong. So on the 700 dragon in 08 thats a touchy era depending on your electrical system I would not go swapping anything electrical unless you are certan its for your vin, year, make model part number tripple make sure for sure! On another theory you could have a crancase leak because its possible the engine may not respond like you would think using the starting fluid vacuum leat trick. At least I wouldnt rule that idea out without knowing for myself is all im saying.

I have other posts on here trying to get anyone to respond that I believe you did respond to. TPS????

 

[Polaridice]

I did notice something that kinda stood out maybe worth a look at what ever is taped up maybe a splice or something gone bad idk? outlined in yellow

 

[Polaridice]

that will be the connection for your injection voltage boost

 

[Polaridice]

As far as your tps goes if you set the voltage and later its off again .. save your self a headach and just replace it espesually if its the original one or unknown condition.
I also recall something with the exhaust temp sensor and needing to unplug it and start the machine and plug it back in while it was running. Maybe someone will have a better recolection on that.

 

[PNW Rook]

I'll check it out thx. Working a lot lately, hopefully get to it this weekend. I'll let you know

 

[Polaridice]

Are you making any headway there guy?

 

[PNW Rook]

I hadn't got back on it yet. I have a lot of time off this coming month. If I can't get it..... to the pros I go.... crap

 

[PNW Rook]

Well I hate to do it but I finally listened to others and bought some starting fluid. The clutch side crank seal appears to be bad. Hosed it down and my idle went from 3200 down to nearly killing it as I held it there. $850 just in labor, I really want to do it.i just don't have the facility to do so.