I have a 2007 Polaris Sportsman 800 . Build date is 10-5-2006 , bought new in 10-2007.
In September I had it in the back of my truck , started it to unload it & it started then shut off. It wold crank but not restart . I had to push it out of the truck . After cranking it several times it would still not start . I pushed on the connector to the control box mounted by the fusebox for the fuel injection? Says Bosch on it , and it started . Thought no big deal . See loose connection a lot on cars.
Also this may be coinicenidental but fuel sometimes comes out the overflow tube ? Near the steering stem area , has always done it with a totally full fuel tank bit it's been doing that a lot lately. Leaves a nice wet gas stain on top of the front differential. Notice it when I stop & can smell gas .
Rode 2 days in West Virginia , hard bouncy riding , almost 180 miles total . This quad get ridden fast and hard , it really takes a beating with all the rocks & the high rate of speed I maintain riding over them.
At the end of the 2nd day about 2 miles from where im staying I shut it off to take a break , cranks but no start again.
Pushing on that connector does no good this time . Crank several times , still no start.
Start pushing & pulling on wiring harness for EFI ? Module while cranking , finally starts .
Have started the ATV several times since then to get problem to act up so I can diagnose it
further but it will not act up again. Pulling on the harness does not make it act up so I'm not convinced its wiring or the connector being the problem either.
I ride solo a lot long distances away from civilization and am leery about taking this out again in case it quits for good . ( I have been riding my old P-700 in the meantime).
I am about tear the whole thing apart to look , before I do has anyone else experienced this
before? Is there an ECM, crank sensor , Gas cap or fuel vent issue , Ignition switch or fuel pump issues with this machine ?
I will be checking wiring but that is very difficult when the problem is not active .
Any replies and suggestions are appreciated , thanks in advance, Jeff .

 

Look here on your model under "fuel tank" will show the vent line routing from the tank. Browse This was a common problem that I found that vent lines would come loose causing the gas leaks or the one way check valves would get stopped up. As far as the electrical problem see if the speedo throws any codes. If you have a short it may not trigger a code though.The Bosch unit is the ECU (brain box). Crank sensor is located on the right side bottom of the engine and the harness routes up under the throttle body. You can check for any bare wire/shorts here that could be causing the intermittent problem. Crank sensors can short out also. Also look at the "sticky" post on efi problems in the expert section that deals with the T-bap and Tps harness and connector problems. Also you should hear the fuel pump prime up when you turn the key on plus if you have a fuel pressure gauge and adapter to fit the fuel rail,the pressure should hold 39 psi with no drop or fuel pump could be the problem. Plus check the fuse box wiring connections and see if you may have a problem there. If you can't eliminate any of this as the problem then having the atv hooked up to a dealers Polaris Digital Wrench may save you a lot of chasing around. Usually one hour labor charge from most dealers can track down the problem to keep you from spending hours tracing wires,etc. Efi problems are sometimes the hardest to track down without the proper test equipment. OPT

 

Thanks for the tips , I can use them all . I figured I would be in for a lot of checking out time with this issue.
When the machine was new I put dielectric grease in most connectors & the fuse panel,
it has kept the mud & corrosion out hopefully.
The cooling fan breaker in the pouch corroded after only 1 year & I recently replaced the seized cooling fan with another new spal fan this past fall right before I started having the no start problem.
I believe I have a small fuel pressure gauge with hose that may fit .
I assume fuel pressure regulator is internal in the pump so if pressure drops the entire unit needs replaced?
Not sure how to retrieve codes from speedo , it has not given me any warnings if it's supposed to.
I will look at the other threads you listed , I hope it's a chafed wire /something mechanical and not a module with an internal intermittent issue.
Fun times ahead, thanks again !

 

Have the machine in park.Turn the ignition on 3 times within 5 seconds. "wait" will show then any codes will show up,then it will show "end" If the problem is a short it may not trigger any codes. Regulator is built into the pump as an assembly,but I've read that some have found a separate regulator that would work.Plus after market Airtex fuel pumps are available.Similar to this. Airtex Master/Fuel Pump (E8197H) | AutoZone.com The most common problem we had at the shop was T-bap harness problems along with a couple chaffed crank sensor harness wires. OPT

 

This is the result I got ,
Turn ignition on ,says Wait , Check engine light flashing while wait appears , then flashes 5 times after wait appears , stops briefly then flashes once more , then end appears .
Code 5 1 or 6 1?
Does that make sense ?
Have to go to work now , can't play with it untill later .
Thanks - Jeff

 

51= Injector 1: Open Load
51= Injector 1: Short Circuit to Ground
51= Injector 1: Short Circuit to Battery


Code 61= end of diagnostic

 

Code 51(injector short to ground or battery) is usually like code 21(loss of synchronization) that appears often and are usually bogus codes. Disconnect the negative battery cable to clear the codes and check again.I've had these two codes come up numerous times on good running machines and also on ones that ran crappy,but they weren't in the problem area. OPT

 

Thanks guys, I will clear the codes tonight when I get home & try it again & see what happens.
Since its currently starting and running ok at this time I dont expect it to throw any codes. If it stops raining long enough to ride it around the neighborhood I`ll truy that also and see if it picks anything up.

 

Try wiggling the wires around on the T-bap harness that's mounted on the air box boot and see if you can get the engine to run different. Plus check for any bare or soft wires(internal breakage) on this harness and the Tps sensor harness also. This is one of the things that happen with these is that they run good one time and spit,sputter,die and run crappy the next time out. Plus don't overlook the crank sensor harness wiring by the starter and the connectors themselves for any wires that may have pulled back a little not making a good contact. OPT

 

Update - Had roofers come to do my roof & packing for a weekend camping/riding trip so I Haven't had much time lately to look at it , went to move it last night and it started and promptly quit . Drcided to stop what I was doing since it finally acted up & mess with it .
.
Turned key off then on , can hear clicking relay in fuse panel but cannot hear fuel pump . Start pushing & pulling on wiring harness at the ECM and fuel pump kicks on , starts up , some more pushing & pulling & it stalls . Turn ignition key on & the relay clicks but no fuel pump prime/whine . Did this several times , it's definitely the wiring harness or bad ECM terminals & probably not the fuel pump itself.
Also returned coding 51 and 52 during self diagnosis & it even showed the trouble codes in numbers along with flashes.
Won't start at all, can't hear fuel pump now without shoving hard on the harness up into the ECM. Connector is not corroded . It probably finally broke the wire internally with all this tugging& pushing / pulling on it . One last shove on the harness & it all works again, appears the break in the wires is where it 90 degree turns just before the connector for the ECM . Wiring appears to be very thin gauge wiring.
Looks like I have broken internal wiring , need a new wiring harness , re pin the connector or need an ECM .
I need to find a wiring diagram & start with overlaying the harness probably from the relay box to the ECM is what it's looking like or see if a replacement harness is available at a reasonable price .
I am going riding this weekend on the Kawasaki so when I get back I will strip down the Polaris & look at all the wiring trouble spots.