04 800 DET issue

My flat land sled is an 800 Switchback. I blew a belt a few weeks ago, put a new belt on and rode it 8 miles home but over 7k the det would flash. Tried new det sensor and checked for vacuum leaks-no change. Turned out the crank broke in the pto journal but I dropped a piston before figuring that out. New crank, case done, 1 cylinder & piston etc. First ride out with it last wknd and the light still flashes. If you stay at low speeds/rpms it is fine. Was able to run wide open a few times for 5-10 seconds and then it came on. As the day went on you couldn't get over 7 period and it came on. 500 mains, needles at 4 and pto side has a shim under needle. Staked the stator before removing it so timing should be good. Running premium fuel premixed for even for the first tank. Running the key in either position doesn't change anything. Anyone got any ideas? I am going to borrow a cdi box from a friend on Sunday and see if that changes anything.

Been running 500's since I bought it. SLP pipe, intake, and gutted air box. Oil in the fuel will lean it out? I thought just the opposite.

X2Freeride said:

500's are way to rich. Im running the same setup as you at 1200-1400 elevation runing 460 mains. Remember gutting your air box makes you RICHER so your probably jetted like 520N or more comparable with a normal air box. Try running 480's and down your sled will run alot better.

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480's are the stock setting for here. SLP wants 2 overstock. I've run this setup for 2500+ miles.

Replacing a couple loose exhaust springs and resiliconing them to elimate and vibration. Have a known good DET sensor to try also if the springs are the culprit. Have another CDI box to try tomorrow from a friends RMK. If that gets me nowhere......:face-icon-small-fro

theultrarider said:

I had the det circut go bad in my 03 escape cdi box. Took waaay to long to figure that one out as it was intermittant on mine. Swap the box with a known good one and pray that is your problem.

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That is the way I am leaning as it isn't always instantly on WOT, sometimes can run 90+ for 20 seconds or better. Also, it has kicked in at low speeds burping it in deep snow playing.

Hey, thanks guys. Once this thing is fixed I got the first round:face-icon-small-hap