Whazzup! This is my first post I came across this awesome forum looking for answers to my problem with my '03 AC 500 auto...I hope you all can help..


Last summer I had a problem with my AC. It would run GREAT until I got around 10-15 miles on a trail and then it would Loose almost All power and you could not get up to 20 MPH or go up a hill or it would try to shut off and then backfire like crazy!!! The power would like Surge and gergle. Funny thing was I would go to a creek and play in it and it would do Ok for an other mile and it would start again.

So I took it to the AC Dealer twice and both times that he worked on it was for 2 weeks and basicly said he found nothing wrong with it. So I took it on a trail and started the same thing. I went home and cleaned the Air Filter, made sure all the wires and hoses was in place and took it for a ride again. By this time it was deer season and I never gave it another hard run, I thought it was fixed since everytime I took it deer hunting it didn't mess up.........

Mostly using my AC for deer hunting I thought Cleaning the Air Filter fixed it all....

Last tuesday I went on a good ride with some friends...went 31 miles NOT ONE PROBLEM!!! The outside temp HIGH was only 45....

Last Saturday I went to on another good ride..went 42 miles...on mile 21 it started AGAIN!!!!! The outside temp high was 65... the Air Filter was not that dirty....so I knew that was not the problem.....

The temp light does not come on like it is too hot...

It seems like it really startes when I got on trails that I need 4 wheel LOW on to go UP Steap hills....

Now the dealer that I bought It off of has sold out to an other guy and he don't fix the bikes...he has them shipped off....I called an other dealer and since I didn't buy the bike from him he don't want to deal/help me....


I hope someone here can help me!!!!!

 

maybe ask a dealer that works on ac and ask him if the heat senser could be the problem. a thought i have is: i wonder if the senser is telling the bike to shut off b/c its getting hot (kinda like when certian engines shut off b/c of no oil) and starts backfiring b/c of warm air from the engine is being sucked into the air intake. i know you said the light does not come on but that dont mean it works either. when you go riding in lower temps it may not get hot enough. high temps, the bike gets hot faster especialy in low from high reving rpm's. this is just a thought and i am not a mechanic,but sometimes its stupid little things that make everything go wrong. good luck and if you find out what it was, please let us know.

one more thing, maybe it has the wrong size jet. just a guess.

 

I'm not sure this is on point, but your symptoms sound familiar.... I used to have a dodge truck that would do just as you described. Turned out to be a faulty solid state ignition module, a.k.a. a black box. When it was cool, the truck ran like a top... but let it heat up, either by working it (towing a boat) or when it was just plain hot out, it would run like crap and then stall. I'd sit for a half hour and all was well... til the next time. The black box controlled the timing advance as well as other stuff. Only replacing it solved the problem-

Just a thought

MB

 

Fuel problem? Almost sounds like there could be a slug floating round in the carb.

Also, you didn't say how long you've owned it or if it sits over winter. I.E. I bought my '03 500i last summer but the date of mfg was Dec'02. It sat a long time. Time enough for the fuel to "go bad." Could you have a similar issue?

I only use my machines for about six months per year and always begin to use Sta-Bil fuel stabilizer a month or so prior to putting them up to ensure all my fuel, storage and in the machines, is treated.

CD unit? Possible heat related internal CD electrical issue? I'm just guessing here.

There are a lot of very knowledgeable people on this forum and one is sure to weigh in with help. Let us know what you ultimately find IOT fix this.

Jim

 

Thanks for the input guys....

REDRYDER- I have thought of something like this could be the problem.....would it make any better sence if I said the Fan doesn't come on that much... when it does the jerking and and going on, I can turn off the engine and the fan will run only for a few minutes...is it suppose to run longer? This would make me think eather..

A.) The engine isn't hot enough to make the fan run that much....

or

B.) A sensor is messed up telling the engine it is not hot...when it really is....

MBullism ---- I have thought of this as well.... maybe something to do with the ignition..????


JimJa ---- I usally run my bike 2 times a week..even in the winter and summer... And I fill up my at diffrent gas stations and this still happends....Thought it could be bad gas at one time....

I did see this thread and wondered if it was the same problem or not.... what do you think???



In this tread a guy is having a simular problem....and I wonder if my gas tank is getting to much pressure in it....when it is hot the gasses will make more pressure...kinda like a HOT COKE bottle....??? What do you think?
http://forums.atvconnection.com/mess...word1=Problems

 

it almost sounds like a bad overheat sensor. But if you're saying the fan doesn't come on too often, maybe it really is overheating and tripping the rpm limiter. I'd check the sensor and/or fan.

 

The overheat sensor does not shut the engine down or do anything other than light up the over heat light. It is either fuel, as in lack of it, or spark. If it is fuel, try putting on the chike a little at a time until you get full choke to see if this changes the problem. If this improves it or even changes it you know you have a carb issue. If it has no effect you can assumme that is is electrical. Spark plugs have been no to ground out intermittently before so try so try anew plug. Beyond this I would suggest that it is the engine speed governor likely sensing high RPM's and retarding the timing effectively maxing out on RPM. Is then engine cutting out at high RPM or under heavy load?
Jim

 

The electronpcs in the ignition module don't like getting real hot. Sometimes a part in the box get faulty and heat will soak into tthe unit and the part malfunctions. It's probably not a fuel problem, it would happen more sporaticly and not get better with playing in the creek (another reason why it sounds like a heat problem. I have a infar-red heat sensor ($49 at Sears) that I use when I suspect these problems. Tells you right now what's going on and worth the money.

 

Vapour locking??

 

you know mbullism... now that you mention it, my 93 dakota did the same thing. it also was the computer. to answer the question to cruff; my fan after shutting it of runs for about 3-4 minutes depending how hot it is out side. i live in missouri so it varies every day. i also will have to agree with bear4570 something with a heat related problem. if it were a fuel problem it would happen right away all the time, but you said it only happens when under load (hot) or on hot days. playing in a creek cools it off for enough time till the steam or heat from the engine efects something to trigger the bike to act funny.(back fire,sput,ect...) this is why i think it may be heat sensor or possibly the computer like mbullism described.

again its probably something stupid and little,good luck!!