Hi all,

I have a very strange idle problem that the machine has had since new. I have a 2012 Sportsman 800 efi. I bought it in February of 2012. I could really use some help. Sorry it's so long, but I want to paint the full picture.

First time I went out for an all day ride was probably around June. We rode from 10am until about 5pm. As the day wore on, the idle would slowly drop. In the morning it was dead on at 1150rpm, by the end of the day it was around 900rpm. It smelled like it was running very rich, almost to the point of noxious. Also, seemed to smell raw gas. Thought it might be the vent giving off the raw gas smell.

Next day at home, it started right up and idled at 1150 - 1200. Did smell like it was running very rich though. Thought the whole idle thing was just a fluke. Couple weeks later, did same all day ride, and by the end of the day, the idle was back down around 900. The whole time it has the low idle symptom, it otherwise runs great. Terrific power and very smooth and strong.

Took it to the dealer, under warranty. They found/said nothing was wrong. This is also when I found out that unlike a car under warranty, if they find nothing wrong, I have to pay the labor bill, not Polaris. $130 later I had no solution. I told him it seems to be happening when it's hot. He let it idle all day long, no problem.

Couple weeks later another all day ride. Same scenario only this time at the end of the day, it wouldn't idle at all. This time I took several videos of the machine idling low and then shutting off. Took it back to the dealer. This time, when he started it to get it off the trailer, it was still idling low; so he verified there was a problem. Though the TPS tested good, the tech grabbed a bad one to send to Polaris for a warranty replacement. He really thougth it was the TPS. I did get my money back and thought we were fixed.

Well, it still does the same thing. Rode all summer with the problem. Don't know if riding it in the heat is any different than just letting it idle in the heat, like the dealer did. Winter cam and I plowed with it. It ran fine the whole tme, all winter. Although it does still smell like it's running very rich. Next summer (2013), same problems. Now it's out of warranty, and I hate to pay them to putz around with it because they seem to have no clue what's wrong.

Again, just this past winter, plowed and rode with perfect idle. So, it seems that as the summer riding day wears on, and things get hotter and hotter, the machine begins to idle lower and lower. Once it cools down over night, it's fine again.

The scenario is like this. Start riding around 11am, idle good, though it does smeel rich. Around noon or 1pm, idle is down to about 1050 - 1100. By 3pm, its idling around 970 - 1000. By 5 pm it's idling around 900 - 950 or lower, or just won't idle at all. During the day when I come to a stop, I do sometimes smell what smells like raw gas. Even saw some gas drips on the u-joint at the front transfer case. Figured it was the overflow or vent purging a little. Again, the whole time it has the low idle symptom, it otherwise runs great. Terrific power and very smooth and strong.

I've checked the TBAP wires, wiggling while idling, but do not notice and change.

Anyone have any ideas as to what could cause the thing to idle lower and lower on warm/hot summer days, but be fine all winter? Summer riding season is approaching and I'd really like to get this figured out.

Thanks for any help,

Mark

 

Bump. Maybe Old Polaris Tech will see this and be able to help you out.

 

Read the "sticky" post above this section on 700/800 efi problems. Common complaint on running rich,erratic idle,dying when the thin harness of the tbap(map) sensor and tps shorts out. May not have visible bare wires,but they can break internally. Usually you can feel soft wires in a harness if they have shorted out internally. Plus the stock Polaris connectors are junk also. I replace many of Polaris "repair kits" that were nothing but the same thin wires and connectors. Almost all of these failed later and I kept replacing them. There is a link in the sticky post about where to get a better repair harness that solves this. Just read the first couple posts and see how the member solved his problem.Wish I had access to these stronger harness repair kits when I was still working. This is his link to the stronger kits. Only The Best

 

Thanks guys, I did read the sticky a while ago, and then before posting. I wasn't sure if that was the problem because I have no codes, no check engine light, and couldn't feel any stretch in the wires. Although that test could be subjective, depending on who's doing the stretching. LOL. Also, when I wiggle the wires, there's no change in the idle. I guess I could just replace the harness to be sure. Finally, since the problem has ocurred since new, I didn't think the wear/vibration causes could happen so fast. Could be wrong.

I thought maybe the fact that it runs great in the winter, but once summer heat hits it changes might be a clue to something different. Also the fact that in the morning it idles fine. But, as the day wears on, it idles lower and lower.

Could the engine temp sensor be a problem? The fan does cycle on and off, and the engine never overheats. Is it a pass/no pass type of sensor? Meaning, it's either good or bad, for every function it serves?

 

You wont always have codes showing if it is a short in the wiring.As far as the thermistor sensor it completes the path to trigger the fan. As long as the fan kicks on,no overheating,it's doing it's job. Plus you can always do a fuel pressure test to see if the fuel pump is holding 39 psi without any drop whether it's hot or cold. A few,not many 800s suffered in hot temps because of the exhaust heat shielding under the tank was a little thin causing problems like you described also. You can add some extra reflective sheathing and see if this helps.If this doesn't help,plus pump is holding good pressure, then I'd still suspect a harness/connector problem.

 

Thanks for your insight. I just ordered both the TPS and TBAP harness. Figured even if they aren't bad yet, they probably will be eventually.

Along the lines of heat shielding under the tank. A thought came to mind. As i ride all day, I'm using fuel. I don't believe I've ever refueled and then went back out. Usually finish the day with less than a half tank, more like a third. Perhaps the reduction in fuel volume thru the day is allowing the smaller amount of fuel left to take on more heat?

Either way, I'm replacing the harnesses. Unfortunately, here in Ohio it will probably be a little while until we see the 80+ degree temps for me to test it all out. May be a little while to accurately continue troubleshooting.

Thanks again for all your help.

Mark

 

Well, I ordered both the TPS harness and the TBAP harness from OTB Powersports. They arrived today. Unfortunately, the TPS harness plug end came crushed.

We'll see if I did the pics right. There should be 5 that show up in this album:

http://www5.snapfish.com/snapfish/th...NAME=snapfish/

I did install the TBAP harness; piece of cake. Come summer heat, I'll be able to test it out.

While installing the TBAP, I noticed that TPS harness plug on my machine is completely different than the one sent by OTB. Mine is more triangular shaped, as you can see in the pics.

Did Polaris change the TPS? This is definitely different. I wonder if they finally figured out they had problems and designed a whole new TPS and harness. Anyone else run into this?

I emailed OTB first, explaining I needed a replacement for the damaged harness. Then a couple hours later emailed for return instructions. Hope to hear from them tomorrow.

 

Triangle shape tps connector hasn't changed. They sent you the wrong connector end. Funny though the picture of the tps connector is wrong on the website,BUT when you click on the picture it shows the correct shape,but the pins are wrong? Hopefully they will straighten this out for you.Again most of the problem we had were on the Tbap only.

 

Just an FYI, OTB replied first thing this morning and I had my refund in my PayPal account minutes later. Good doing business with them.