Hi Guys, I'm back. I've put about 2000 more miles on my Sportsman...I still love it! Anyway, recently I have noticed a small to mediocre loss of power after riding a few hours on the trails. Here's what it does. When I'm on the trails and just meandering around it seems fine, but when I get into and area where I can open it up a little it bogs down from the start but will pick up speed. Not nearly as fast as it should though. SO after much reading, I finally resolved to get a fuel pressure tester to test the fuel pump. OK, so when I first start it up cold, it springs right up to 40PSI and holds like a champ. So I decided to take it for a ride while the gauge was on there. It ran between 39-40PSI for about the first 30-45 minutes. Then I noticed that it would gradually decrease. I seen it lose a couple pounds when the cooling fan would kick on, and also at least 1 PSI when I would pull the front break lever inciting the break lights. Ok, so after about an hour and a half, the pressure gauge was fluctuating between 26-30PSI. SO I thought there it is, I got on a straightaway and extended my throttle thumb as far as it would go. I was expecting it to somewhat fall on its face...this was not the case at all...it tore the freakin road right up... So I took it out on the highway and got up to 60MPH for a while, all the while keeping as much of an eye on the pressure gauge as I safely could. Then stopped on a side road and tried to hammer down....she took off like a rabbit once again...ok, fuel pressure is at about 22PSI at this point and it runs like it's brand new...I am sooooo confused. MY only thoughts are , maybe I need to ride it longer to get it to reproduce the experience I had before. Oh, also, on a side note, if this was just an isolated incidence, then I would not be concerned, however, I have experienced it at least 3 times. Any and all comments welcome. Thanks in advance.

 

About all I can say is that tests are supposed to be taken with the engine off,but with what you've done even if it did run ok with 22 psi sounds like a fuel pressure regulator problem in the pump assy. They weren't offered before,just the pump,but are showing up on ebay. You might keep this in mind if it really starts acting up.http://www.ebay.com/itm/Polaris-Sportsman-700-800-EFI-Fuel-Pump-Fuel-Pressure-Regulator-39-40-PSI-/161673944786?hash=item25a4849ed2&vxp=mtr

 

Thanks old polaris tech, I did forget to mention that I tried the test with the engine off. I would turn the key on and the pressure would peak at around 40PSI when cold, then drop to 0 PSI immediately. When it was hot, it would spring up to 20PSI then right back to 0 PSI. No matter how hard I try to remember everything I do, I have to face the fact that I have "old man brain" and tend to forget things....lol

 

Some other things I forgot to mention, I have checked and cleaned the T-Bap (using electronic cleaner, it actually didn't even look dirty, but I had it out so I cleaned it anyway). I have pulled the throttle body off and cleaned it as well. Made sure the air filter is clear of anything that may clog it. Although I have been thinking about replacing it. My local Yamaha dealer said that those are re-oilable (not sure if that's a word or not) but it really looks like a simple paper filter to me. I looked it up online and it is an authentic Polaris air filter. I can't think of anything else I may have done at this time, but again, I remember that I got "old man brain" too.

 

If it dropped to zero,might be best to get a cheap pump and regulator and at least eliminate a fuel problem. http://www.ebay.com/itm/INTANK-FUEL-PUMP-FITS-POLARIS-SPORTSMAN-800-EFI-2005-2006-2007-2008-2009-2010-/271408156441?hash=item3f312fcf19&vxp=mtr Plus if you ever suspect a connector or wiring problem on the sensors,remember this place.Only The Best

 

So here's something interesting that just happened. My wife and I took the Polaris downtown for a quick ride through the rally (75th Annual 2015 Sturgis Motorcycle Rally | Black Hills Motor Classic | City Of Riders | Events | Concerts | News | Guide | Lodging | Webcams) if you're not familiar. Most of the traffic during the Sturgis Rally is stop and go...or more like stop, wait, then go. Anyway, as typical with the Polaris, my right leg was getting excessively hot from the exhaust, it didn't help that I was wearing shorts either. Well after about 30-40 minutes of this stop and go traffic, I made a right turn from a stop sign. As I turned right and accelerated the Polaris sputters several times and popped off through the exhaust. My first thought was that it was just loaded up and needed to breath. They're not really designed for that kind of use. So we went a couple blocks at 25-30 MPH, then stopped at another stop sign, then made another right turn. Same thing. I stopped at the next stop sign and tried a left turn, ran fine, no problems. We drove it home after that without incidence. ( I live about 5 miles from town on a canyon road. 45MPH speed limit). Tried to get it to do the same thing in my driveway/yard and it was fine. Whatchya think that might be? Fuel pump perhaps, or crimped vent tube. ( I actually loosened the gas cap after the first time it sputtered and backfired)

 

Possible you could have an intermittent wiring short to the tbap or tps sensors. Common problem on back firing,running erratic also. Look over this web site,explains some of the symptoms,plus the manual even says 80% of efi problems are because of sensor wiring,that is if you've eliminated and fuel pump related problem.Plus codes may or may not show up on wiring problems.Only The Best

 

Hi old polaris tech, thanks for all your help. I appreciate it. As a matter of fact, my last year of riding my Polaris is a direct result of your experience. Anyway...enough butt kissing....lol. Last week when I started noticing some problems arise, I checked for error codes on my diagnostic screen. There were none. I haven't ridden it since my last post and went out to ride it today, but first I decided to run a diagnostic on it. I was surprised, I got error code, 45, 41, and 25. In that order. When I looked up the error code 45, it was obviously the T-BAP. I kinda figured that already, I thought I had seen that one somewhere before. When I looked up error code 41, it refers to the "Air Intake Temp Sensor"...ok, that one is a little more elusive. I have to admit, at this time, I am somewhat confused by what I am reading on the internet. Is the T-BAP and Air Temperature Sensor the same thing? So moving forward, after the diagnostic completed, I shut the key off and tried again, same thing. But this time after the diagnostic completed, I started the machine and run it for less than 30 seconds. When I ran diagnostic again, all I got was error 25 at this time. On a side note, from what I understand, error 25 has something to do with the gear selection and/or belt, which I believe I will be replacing here shortly anyway as I am experiencing some "creep" in reverse and low gear. (Please correct me if I'm wrong). I've checked out the "Only The Best" website, and I think I will order the replacement harness for the T-BAP. Is this a complete harness, or does it hook into some more Polaris wiring? What I mean to say, will there be more wiring that could possibly be the problem, or does this go directly to the ECM? Sorry, I haven't researched it as much as I probably could. I've also got the cheap fuel pump and strainer on order that you suggested, along with the pressure regulator to rule out any fuel pressure problems. I have to assume when I take the fuel pressure reading that once it hits its peak, that's where it should stay. I only assume this from my experience with taking compression tests on car cylinders. Sorry for the rambling, my brain is going 180 MPH in 3 different directions.

 

Code 45 is the main one you've hit.Tbap sensor problem. Just check it out,get a good replacement from otb.Not all codes such as code "22" loss of synchronization,etc or even codes for the "air temp" sensor(41) in most air boxes are good codes.Some are bogus.You can check the sensor itself,clean it if you want to on the air temp sensor. Don't think I've ever had to replace one or even a wiring kit for one,but anythings possible concerning wiring. Hopefully this one will solve the problem.It has the connector and wiring(about 8 inches I believe) along with connectors and shrink tubing. Just ties into the main wiring harness.Just like the Polaris kits I installed,but stronger. On fuel pressure tests just turn the key on don't start it.Some testers have a bleed valve and hose like we had. You may have to open and close this valve to get the air out of the system along with a little gas,then on final close the pressure should be around 39-40 psi with no appreciable drop.

 

So I got the wiring harness from OTB and put it in. At the same time I got some titanium exhaust wrap and hi temp header paint. Sanded & painted the exhaust ( to help avoid corrosion) and then wrapped with the titanium exhaust wrap. Still waiting on my new T-BAP/T-MAP sensor to arrive. I found something interesting yesterday though. My wife and I went for a ride around town to survey the damage left by the 1+million bikers that invaded our town of 6K people. I noticed that I was still getting the sputtering while turning to the right, the night before last I took the dash console and adjoining parts off to inspect the wires for looseness and shorts but found nothing. But anyway, when we got home, I stopped at the back deck to let my wife off before I went and put my Sporty into the garage. When she got off I , for some reason, decided to rock the ATV side to side. When I rocked to my left, which would emulate a right hand turn, the engine flat died! The instrument cluster was still lit up and the cooling fan was going. The engine started right back up when I turned the key. I tried this a second time, it died again. Ok, obviously there is a short somewhere that I am going to have to hunt down, maybe the ignition coil is loose or something of that nature. Anyway, I hope to fix it this week because my wife's and my anniversary is this weekend (23 years) and there is a ride sponsored by the Soggy Bottom ATV/UTV Rally that we wanted to attend this weekend. (if you're on Facebook: https://www.facebook.com/pages/Soggy...019776?fref=ts )
Anyway, just throwing this out there to see if anyone may have any ideas. Thanks for any help in advance.