Polaris ATV Forum banner

21 - 28 of 28 Posts

·
Registered
Joined
·
41 Posts
Discussion Starter #21
I like this idea. My wife's identical machine does the misfiring just a tad. Mine does it a lot. Never backfires. I wish they both acted the same. I'm going to pass the majority of your suggestion to the service leader and to MN Polaris. It is time for engineers at the factory to get involved.
Thank you,
Greg
 

·
Registered
Joined
·
23 Posts
My 2020 570 eps was doing that, constant throttle it would spit about every 3 seconds almost like I was decelerating, it finally quit after about 10 hours and a few wide open throttles. Now it’s smooth as butter. I think it has something to do with the fuel they put on them at the dealership and just let them sit there.
 

·
Registered
Joined
·
41 Posts
Discussion Starter #23
Ok, misfire mid-rpm problem finally solved! Here's a good one for you all....the factory lead the troubleshooting with the local dealership. In summary,
1) A new throttle body was pulled from a crated machine and installed on mine. No changes to the misfires. Original throttle body re-installed
2) A new ECM from the same crated machine was swapped with mine. No changes to misfires. Presumably (?), my ECM was put back in place with another test drive.
3) BOTH the same crated machine's throttle body AND ECM were simultaneously put on my machine, and problem solved.
I brought it back home today and did two short rides, and it ran flawlessly. About 8 hours and 100 miles on the almost new ATV.
The talented and head of service guy here has no clue why this fix worked (nor do I). And, obviously, the factory rep knew to suggest trying the 'matched' pair from the crated machine. I talked with another factory service guy who was substituting in for the main factory guy, and asked him if my [bad] parts were going back to the factory for root cause analysis, and if I would be able to get an answer as to why this worked. He said "we don't share that information".
What surprised me is that there would be some difference between my ECM and the crate ECM. What wouldn't surprise me would be cost cutting measures to produce a less expensive throttle body, and make up for this with the programming (ECM). What I'll never know is if there was a different code set between the ECM's.
Thoughts?
Greg
 

·
Registered
Joined
·
140 Posts
Ok, misfire mid-rpm problem finally solved! Here's a good one for you all....the factory lead the troubleshooting with the local dealership. In summary,
1) A new throttle body was pulled from a crated machine and installed on mine. No changes to the misfires. Original throttle body re-installed
2) A new ECM from the same crated machine was swapped with mine. No changes to misfires. Presumably (?), my ECM was put back in place with another test drive.
3) BOTH the same crated machine's throttle body AND ECM were simultaneously put on my machine, and problem solved.
I brought it back home today and did two short rides, and it ran flawlessly. About 8 hours and 100 miles on the almost new ATV.
The talented and head of service guy here has no clue why this fix worked (nor do I). And, obviously, the factory rep knew to suggest trying the 'matched' pair from the crated machine. I talked with another factory service guy who was substituting in for the main factory guy, and asked him if my [bad] parts were going back to the factory for root cause analysis, and if I would be able to get an answer as to why this worked. He said "we don't share that information".
What surprised me is that there would be some difference between my ECM and the crate ECM. What wouldn't surprise me would be cost cutting measures to produce a less expensive throttle body, and make up for this with the programming (ECM). What I'll never know is if there was a different code set between the ECM's.
Thoughts?
Greg
Greg,
Based on your description I'm trying to understand the basic logic of what the dealer did. Let's also proceed on the basis that they potentially didn't tell you everything that they did as well.
If it was something as simple as reflashing the ECU I'm sure they would have tried that...so let's say that they tried that and that obviously didn't work. So programming may have not been the
issue if they swapped a brand new 2020 updated ECU with your 2020 updated ECU. So, by putting the new throttle body on from the machine they grabbed the ECU from...I'm assuming that
the IAC and the TPS sensor were from the other machine as well. It might have been a bad TPS sensor or IAC on your machine that was rectified by swapping out the throttle body. Just food
for thought. If you weren't in the shop the whole time it's real hard to verify what they actually did versus...the lip service that they give you once the problem is fixed. I get it...the machine is under warranty...so they are obligated to fix it..and all you want to do is ride the expensive toy that you can't ride.
Personally, my machine is a 16' 570 and I've had it to the dealer a couple of times since it has been out of warranty...but no matter where I bring it...I always feel like I'm getting screwed royally with
half ass workmanship at outrageous labor costs.
So, I decided..screw it...and bought the service manual and bought the OTB diagnostic tool that hooks up to a laptop so from now on I can diagnose and fix the majority of my own problems, source out the parts at a fraction of the cost, and not deal with the rape artists at the dealer.
 
  • Like
Reactions: RoyR80

·
Registered
Joined
·
41 Posts
Discussion Starter #25
Good thoughts. I'm going to side with the dealership on this one. The diagnosis was run by the guy in charge of the service dept. We came by five years ago with our 2015 570 which wouldn't re-start when hot, but did start after a half hour. After a few of his guys looked at it and shook their heads, he says "I have an idea". He traced the fuel overflow tube to a pinched spot at the front of the frame, and nailed it. Re-flashing the ECU was the first thing tried before involvement from factory. I'm under the impression that turnover rate is high among service techs.

Back to understanding the issue recently solved. Because the folks in the forum here, the dealership, and I have invested so much time into this, I still want to get to the bottom of it all. I'm tenacious. I have my old expensive 2015 570 manual, popped off the seat of these 2020 570's, and verified that the new throttle bodies are very similar to the ones in my manual. Please critique:

Throttle body: there's the rider-controlled throttle cable coming in on the left, and TPS/IAC sensors on the right. The TPS ("Throttle Position Sensor") measures the throttle plate position selected by the rider's thumb. This is one signal sent to the ECU. The IAC ("Air Idle Control") sort-of-bypasses the TPS to control idle at cold (start up) and after warm-up. The TMAP (mounted between throttle body and engine intake) senses the passing of air and manifold pressure. I have the advantage of comparing our two identical new 570's, and it looks like the TMAP sensor was never messed with during the entire diagnosis process. Same dust in same spots.

The ECU receives (among other inputs): crankshaft position, engine speed, throttle position (from TPS), coolant temperature (same on both machines), air intake temperature (from IAC?), air flow (from TMAP), intake manifold absolute pressure (from TMAP), and battery voltage. This data is mapped to some constants in the ECU, and the output is fuel injector action.

My goal is to have an intelligent conversation with the original factory guy who led the effort and see if I can understand why, after recommending separate swaps of throttle body and ECU, why at the end would recommend going back and swapping both as a pair. At this juncture, I wouldn't be surprised if there are enough differences in throttle body production variances that perhaps there's a constant mapped into the ECU that matches ECU to two or three different performance aspects of throttle bodies. When reflashing, this constant would be left alone.

Where did you get your OTB diagnostic tool, and if you could share, the cost?

Greg
 

·
Registered
Joined
·
140 Posts
Greg,
I think you have a pretty good grasp at this point of the "workings". Your're probably right with your statement "At this juncture, I wouldn't be surprised if there are enough differences in throttle body production variances that perhaps there's a constant mapped into the ECU that matches ECU to two or three different performance aspects of throttle bodies. When reflashing, this constant would be left alone". At least the problem is solved and your back riding again. But I'd be the same way...I'd want to know exactly what caused the issue and why.

As for the diagnostic tool, I bought directly from their site for $399.00, plus you need your own laptop. The tools allows you to read any codes that may be popping up on your machine (whether they are being displayed on the machine console or not) and through the software it gives you step by step on items to check that could be causing the error/code. It also allows you to view all of the important info in real time whether the machine is running or not to help make sure things/settings are where they need to be. As per the statement in the service manual...most of the EFI issues are electrical/wiring related. It helps track down problems quickly. OTB also sells replacement heavier duty "splice in" wiring pigtail connections that go to the various sensors/connection on the machines. The cheap Chinese wiring on these machines tend to be a problem down the road (like I said mine is a 16' and I just started having wiring issues this year)

 

·
Registered
Joined
·
41 Posts
Discussion Starter #27
Thanks Nbonugli:
I've got a call in to the factory guy with my seven digit reference code. And I hope I can get more detail.
We've found our best trade-in point for these--we ride them about 300 hours and 3000 miles, and at that point, they're a year away from needing new tires and a brake fluid flush, and they still jump a bit when the clutch grabs the belt starting out in H or L, so the belts are still reliable. For the most part, these have been reliable machines with good power and suspension. And thank you for the tip about the diagnostic tool. Sounds like a good investment, and I hope will work with other Polaris', as we have a number of Razors in our group. Chinese wiring....uggh....hopefully that commitment will end soon and it'll get done here in the USA.
Greg
 

·
Registered
Joined
·
191 Posts
A long, long time ago I worked as a tech at a SAAB dealer. We had a car that would start and rpm would fluctuate at idle when cold. The fix was a new ecm that was delivered by the factory rep.

I am guessing something was in that particular one that wasn't available for general deployment.

This was back in 1989.
 
21 - 28 of 28 Posts
Top