• We have updated the site to the latest version. You will be required to log in to make sure your account is active. There are quite a few new functions so it will take a little time to get use to it. Please post if you see or have any issues.

2015 Axys Pro X 800 H.O. DET mode issue

wallacbr

wallacbr

New Member
Messages
28
Age
40
Location
Wisconsin
I'm getting the DET alarm every time I go over 3/4 throttle and then the sled is going into limp mode. I have to restart and then it will run fine until I push throttle past 3/4 again. I've had the sled at the dealer twice now to work on the issue without resolve. We've covered bad fuel, clutches, tps sensor adjustment, fuel pressure, power valve adjustment, ethenol setting and all the items associated with this issue except the DET sensor itself. The fault codes he reported from DR have to do with the knock sensor alarm.

Wondering if there is a way to test the DET sensor in a state of rest or ?? Anyone else run into this issue and how it was resolved? Ran out of snow last season so he couldn't finish. I'd like to get a jump start this year.

Sent from my XT1080 using Tapatalk
 
Just to be clear, have you verified proper fuel pressure at WOT when the DET comes in? A plugged fuel sock would cause this issue, have you pulled the fuel sender out and changed the sock? How many miles on the sled?

Also, is the DET happening on the MAG or PTO cylinder or both? Same all the time???
 
There are lessons on how to test knock sensors on the web.

But. If it's not the sensor...

I wounder if you have dirty or somehow low flow injectors and are too lean on top? Very possible.

Getting your injectors tested and cleaned is probably not a bad idea anyway.

Do you have, know someone or are you willing to buy a wideband oxygen sensor? You could test the lean theory that way too.

Is there some reason your timing might be off?
 
Look at the above listed. and make sure your exhaust can/muffler isn't damaged . Aftermarket can ?
 
Sled is bone stock. Has about 1100 miles. I purchased from dealer as demo sled at the end of last season with 800mi.

From dealer notes: Fuel pressure was 60 psi at WOT for 600-700 feet then it goes into det mode.

DW report shows 23 MAG & 12 PTO codes thrown. (P1337 & P1336)

Some other good items here I'll have to look in to...


Sent from my XT1080 using Tapatalk
 
Ya ck other things listed. Fuel pressure doesn't mean fuel volume is being delivered
 
On the Cat 800 HO, we saw positive results taming the knock sensors sensitivity by re-torquing to a slightly lower value. Over tight = over sensitive.
I'm assuming you've already checked plugs / pistons for signs if it's actually got a detonation issue?
 
Those codes suggest bad fuel, lean running condition, or engine mechanical problems in the manual .

Easy thing to do, siphon old fuel and replace with good known fuel

Check and replace injectors

Check and replace fuel sock

Relearn your valves

Check intake for air leaks

Replace knock sensor

Check crank seals
 
Something simple to check and known issue. Find the exhaust valve actuator follow wiring to upper crossmember of bulkhead. There will be a wire connection, pull it apart and look for any signs of corrosion. If so, clean both sides of the connector, and pack the connector full of dielectric grease. Plus, if the dealer is stumped, he can call tech support to help in diagnosing the issue.
 
Thanks for the great feedback. I have a few items to work on and I'll report back with the findings.

Sent from my XT1080 using Tapatalk
 
JMO> figuring out if the problem is actually detonation (for whatever reason then addressing it) or if your ECU is seeing something through the knock sensor that isn't really there is where you need to start.
In the instance of the 800 Cats, spent way too much time trying to figure out an issue that wasn't really there in the first place (constant Deto light under harder pulls making it appear there was a deto problem). Since so many were mysteriously taking out pistons at the same time, was far too easy to overthink the whole thing and make assumptions. In the end, problems were in no way shape or form related to one another. Re-torque fixed oversensitive deto sensor, bar hone of my own cylinders to correct for nik puddling around the ports fixed piston life. Prior to fixing it myself, engine had already eaten two sets of pistons / one set of cylinders under warranty in virtually no miles.
Wishing you luck with it, hope the dealer is looking after you.
 
Anybody try unbolting the knock sensor and zip tie it off to the side and then try it. I did that to some of my older sleds and it seemed to help. Especially with the edge 800
 
Keep in mind how high strung these engines are, det sensor is a must have to help keep it in one piece.
 
So, I had it at a different dealer to go through all the troubleshooting again and be sure the first dealer didn't miss something. Well nothing was resolved. The service manager who I've been working with said the Polaris technician told his mechanic that "these sleds need to be pounded hard" or else they won't run right. Are you freaking kidding me??!!! He also said that the TPS history showed the majority of the throttle position between 25-50%. I guess implying it was not ridden hard? No kidding, any amount of time spent beyond that and the DET sensor is tripped. The dealer service manager agreed with me on this one and said he was going to call the technician back tomorrow and personally talk to Polaris.....so we shall see.

It seems like they are all making it out to be more complicated that it should be. Normally I would have torn into this myself to troubleshoot things but since it is still under warranty I don't feel I should have to lift a finger....I may be wrong. More to come...
 
That's a bs. Reply for sure. the det isn't a your riding me to easy alarm. Lol. My father would live with the det light on if that was the case. Have they been able to simulate the det. Condition at the dealer ?
 
That has been part of the problem I think. It won't trip unless the engine is under load. The first dealer was able to trip it on the second trip in but there is not any snow for the dealer to test now.

Sent from my XT1080 using Tapatalk
 
That code # you gave was for excessive knock(fuel problems)
Lean running condition or engine mechanical problems

Siphon out old fuel and put in good known fuel

Replace det knock sensor and torque a light 168 in-lbs.

Get dealer to check timing with tps unplugged and engine temp at 120f, it should be 18 degrees from 1300-3000 rpm

if this is all good , go try sled in ethanol mode and hammer on it
 
is your sled used? maybe have ssi pipe mod? mine would DET past 3/4 throttle with pipe mod and if someone didn't tell you you can't tell it had a pipe mod looks stock
 
It was a dealer demo so it's considered new but it had 800 miles on it when I got it. I doubt the dealer himself installed a pipe mod but you never know. Something I will look into. Thanks

Sent from my XT1080 using Tapatalk
 
Anyone know what the resistance tolerance would be for the det sensor at rest? I see the manual shows it at 4.87 mOhms and I'm getting about 5.02. The shop is about 50 degrees F.

Sent from my XT1080 using Tapatalk
 
You must log in or register to reply here.


Back
Top Bottom