The wife and I went for a ride today and on the way back home her 05 Arctic cat 500 LE started to run a little funny. She was going up a sloped road when it sounded like it was only fireing every other revolution. The fastest she could go was about 20MPH up the slope. We were riding for about 4 hours and the thing ran flawless until we were on the way home. Once on level ground the thing would go about 35.

What are some of the things that would cause this issue. We filled it up with super unleaded before we left for our ride.

Could it be fuel pump? Electrical? Any other ideas?

 

Could be that you bought your fuel at the wrong time , what i mean by the wrong time is that the station where you bought your fuel at under ground tank could've been low allowing you to pick up water/trash that settle's in the storeage tank , also they could've just has a tanker load of fuel causing the crap in the bottom of the tank to mix in with the good fuel !

I stopped at a gas station that i alway's bought my fuel from one day and pulled up to the pump while this guy was unloading fuel from the tanker , when i got out of my truck the guy filling the tank's ask me if i had enough fuel to make it untill the next day before filling up ; he told me that the tank i was about to be filling my truck with fuel from was out of gas before he got there.

He told me that all the crap in the bottom of the storeage tank would be mixed up with the fresh fuel he was unloading and go into my pickup , i thanked him for the info and went to another station for my fuel , the guy told me it would take 24 hour's for the crap to settle to the bottom of the storeage tank , my 88 S15 GMC Jimmy 4x4 is sitting in my driveway right now with a little less than a half tank of bad fuel i got at a local Krogers store a week ago it started running funny like your wife's 500 lol the day after the fillup !

My Jimmy has the 4.3L EFI engine and doesn't have enough power to start with , but with this bad fuel towing my 2006 Arctic Cat 400 FIS Auto 4x4 with my light trailer going up the same hill where i could usually run 55 mph would slow down to 40 mph with the pedal to the metal with a whole lot of skipping and backfiring to boot ; yesterday i went out to pay some bill's when i left the last stop and on my way home i just barely got over this long bridge when the engine stalled and wouldn't restart at all ; i was luck enough to get into the center lane to prevent me from causing a traffic jam .

A County Mounty ( Sheriff's Deputy and a local yokel ( City Police Officer ) stopped traffic and the Deputy using his push bumper got me off this busy street into a Title Block Title Pawn parking lot , i thought i had just paid the last bill of the month untill this happened ; to make this long story short lol ; it cost me $40.00 on a rollback to my driveway !

I don't think it would be your fuel pump more likely crap in your fuel tank , or your wife's 500's fuel tank could've been low enough as to not allow the fuel pump suck enough fuel from the tank while going up the sloped road to get over 15 mph , in any case i would check your fuel filter for trash ; i'm not possitive but does the wifes 05 500 have the gas tank up fron't between the seat and handlebars ? If so does it have a petcock to turn the gas off/on/reserve ? If so there's only one filter/screen on the petcock in the on position , the screen may need cleaning , my 2005 AC 400 FIS Model has the fuel tank in the rear between the plastic's and frame ; i don't remember what year this change in the location of the fuel tank !

If it's turn's out that you have bad fuel you'll have a bigger job on your hand's , but it will cost less that a fuel pump , another thing in my 2006 owners manual the fuel reccommended for the 500 is the same as my 400 ; 87 octane regular unleaded i really hope this reply help's you out but it should get the ball rolling and someone with the same model 500 as your wife's !
Good Luck !

williebee......

 

I pulled the carb and it was super clean, all passages and jets had no gunk. I also started to fill my tank then stopped and filled her tank up completely then finished mine off when we got gas. My quad had no problems at all. Thats why i think the problem lies with the fuel pump or electronics. The tank is under the back fenders. Is there a fuel filter between the tank and carb? Maybe that is slightly clogged slowing the fuel down to the carb which is running it low in the fuel bowl? Any ideas of what, where and how to check?

 

My 06 400 FIS Auto 4x4 has the fuel tank in the rear also , i think the electric fuel pump in inside the tank or close to it on the outside of the tank , i know for sure that the fuel filter is under my seat and the fuel sender/senser is inside the tank , remove your seat and if your 05 500 is the same as mine you'll see the tool tray is mounted over the battery held down with 2 hex screw's , and you will also see the battery cable's coming out of the battery box going to the starter relay or seilod ; and the fuel filter is next to the seiold with the fuel line's/hose coming up from the tank 2 or 3 coming from the tank one of the hose is the main fuel line that come's off fuel filter and the other line's are vacume and vent line's .

Then there is the main hose coming from the fuel filter then goes up and around the air intake and plug's straight to the carburator , i had trouble with the fuel pressure leaking back down the hose causing hard starting issue's not long after i bought my 2006 AC 400 FIS Auto; and i am the original owner (first new quad for me ) the fix for mine was replacing all those hard plastic hose that all the manufacturer's have gone to with flexable GoodYear Automove rubber hose and screw type clamp's !

That main hose that came off the fuel filter going to the carb was spliting and slowly loosing pressure , after replacing these hose problem solved , here's a good way to test the fuel pump remove the hose from your carb carefully use a container and place end of hose in container to catch the fuel when you turn on the ignition switch and push the starter button ; you should be able to hear the electric fuel pump running or making a clicking noise when you turn on the ignition switch and push tthe starter button .

That was one of the worse thing they ever did ,(changing from the soft rubber Automotive type fuel , vacume and vent line's ) to the hard plastic line's , this type fuel , vacume and vent line's get brittle and split where the rubber line's last for year's ; i worked in the small engine service abd repair field for over 20 yrs. before the manufacturers switched over to the hard plastic i had to replace the line's at least every year !

Well i hope you get your quad going soon , i don't know where you're located , but where i live in northwest Ga. it's starting to get warm enough that i'm aching to start riding again ; good luck !

williebee........

 

Try a new spark plug

 

Thanks williebee, i will check that stuff out tomorrow and get back with you. Kerbirds, i will buy a new plug and try that out as well, i will make sure i do each item then test so i can pin point the problem and report it so other will know what to look for.

 

Ok, i'm at a loss right now, i checked the spark plug and the color is just as it needs to be, golden brown. The fuel
pump is pumping strong and constant when i had the fuel line off the carb. I couldn't find the fuel filter but the fuel system looked really good and the fuel was not obstructed. I then checked the charging system and with the machine running and it was 14.7. The valves and timing are correct. That leaves me to believe it is the ecu. Is there anyway to check those as they are expensive to replace if that is not it. The carb is adjusted to the manual and extremely clean. I'm at my wits end trying to figure this thing out. Any ideas?