Here's the scoop. I just bought this machine about three weeks ago and it has been nothing but trouble. At first, It was leaking oil from the cooler lines and cutting out and backfiring at low rpm's. So I brought it back to the dealer and they said that it was the ETC, and that they would replace it. I just got it back on Saturday, and now it will run fine for about twenty minutes, but once it gets warm the throttle will cut out at about 2400 rpm and it will backfire through the carb. I'm beginning to think either its a lemon or the dealer just is not fixing what they say they are. Any ideas? I'm beginning to lose hope, since this is my first toy.

 

First off,I would check the valve clearance. .006 intake and exhaust when engine is cold. Especially the intake could be too tight and as it gets warm,even tighter and can cause backfiring,etc. Looking at the electrical schematic don't think was on an ecm recall if its a 2004. If valves are ok,then possibly could be electrical breakdown as it gets hot.May need to have resistance checked on stator,plus the coil. Also check that the coil wire itself doesn't have any bare spots. Plus make sure the throttle has about only 1/8" slack at the thumb lever,adjuster is on the cable down from the throttle housing. Keep us updated. OPT

 

I am moderately mechanically inclined, but have no idea how to check the valve clearances. Also, the coil appears to be new, but i checked the voltage on the battery and it was reading 28.2 volts. I'm not sure what could cause this. The throttle seems to be tight.

 

If showing 28 volts at battery while running,then it is probably the ecm mounted on the front bumper guard,can cause a lot of problems. Schematic shows two different ecm numbers (mfg before 3/31/03 and after 3/31/03) Call dealer with your vin# located on left lower frame behind left front tire etched into the frame as to correct one needed.(probably will call for the newer Sure power module??)
MAJOR recall on mainly 05 and 06 models,But have found others outside of the recall group. The 2004 Atp 330 was different on ecm location than other atvs. Ecm unit controls mainly the fan and charging ,but can screw up a lot of things. OPT

 

Would the ECM cause the problems that I am having?

 

Ecms can cause a lot of problems from overcharging, undercharging,NO fan operation,and can cause machine to completely quit! If you search up ecm problems you can see a lot of things that can happen. On the recall bulletin customers were sent a copy of the safety bulletin instructing them to disconnect the battery in case of catching on fire! This was mainly on the 2005 and 2006 models,but some 2004 models were included.Plus as mentioned,I've had some bad out of the recall range! This may or may not be your problem,BUT battery voltage shouldn't be more than 14-14.5 volts while running! I still would call in your vin# to the closest dealer and if its under the recall,it should be warrantied as this was a safety bulletin! OPT

 

Well, today it goes back to the dealer to be repaired. I will keep you posted on what they say it is.

 

As it stands right now the word of the day is stator. That is what they are going to replace this go around. As for the battery, it was fine. I just used the wrong setting on the multimeter. What can I say, I am a genius.

 

Got it back from the dealer last week. It was a couple wires dropped across the engine and grounded out against the head. runs like a champ now.

 

Hopefully didn't cost too much! Congrats on getting it fixed. OPT