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Hello guys. So I have been doing tons of work on new sled I picked up.
I will tell you what I have done so far and then what it’s still doing.
‘Rebuilt both clutches from ground up new springs Helix on secondary and all.
‘New plugs, new battery, new fuel filters both the small one and the big one.
‘New bearings in jackshaft and drive shaft and bearings and seals in chainecase.
New Stator New CDI box

so only issue I have left that will not go away. Sled starts up purrs like a kitten. It gets warm and I go up on RPM. Runs great as long as I don’t let off throttle. If I stay on sled for awhile run it around it will run fine. But after it warm up I give it gas and let off trottle it will idle down then just dies.
‘After it dies like this you can not crank it no matter what you try. You have to wait 30 mins to 1 hr then you can crank it again runs great till you give it gas and let it off throttle.
‘What is throwing me for a loop is if I let sled warm 100% percent up and ride it for 5-10 min then stop it it’s great stays running.
‘If I turn it off then and I can restart no problem.
‘If it dies though by itself. You can restart it till you let it sit.
‘I have tried jumping out the Estop and TAS switch with a wire. But didn’t help so it’s not that.
‘Anyone have any ideas.
 

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Discussion Starter #2
Also no codes on ECU. I have hooked up Select monitor and put my PC on it with cable. Everything reading great even when it shuts down and will not start.
 

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I had 90, 92 and 95 RXL's and my son had a 92. My 95 we had a problem with but I don't remember exactly what it was. Dealer got Polaris to replace the brain box and they did even though it was out of warrantee at the time.

Sounds to me like that specific sequence keeps the "system" from supplying fuel . When it happens again try pouring some gas in the breather or starting fluid to see if it will refire.

Maybe it is vapor locking in that situation.

Polaris retrofitted a "primer" to the 92 500 EFI sleds in 93 for a somewhat similiar problem.

Grabbing at straws here but you hadn't mentioned trying priming to restart

Good luck.
 

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Yeah I thought it was not getting Fuel either. Thinking maybe by chance it was fuel pump. Even though it runs great at elevated RPMs.
‘So I tried it with gas tank open. Cleaned breather lines, and if you remove the bolts on bottom of the cylinder so you can drain gas out of each cylinder Fuel comes out. So it’s getting fuel. It’s getting spark. And has to be getting air. So at this point wtf is going on. I have actually wondered if something in the EFI is not right. Even though everything has to be kosher for it to send signal to the fuel pump to kick over. Which it does.
 

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Man, there were a few very knowledgeable EFI guys on this site too....sucks to the sad state of the population here these days. You might try over at Snowest or one of the other forums.
 

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Discussion Starter #6
Yeah sucks. I know I am missing something dumb. It has to be something stupid. I am a Computer Guy. I get it. But see nothing that would suspect ECU is going bad except it’s looking that way.
 

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Is it possible the battery isn't being charged enough. Most of the time with the EFI its the battery. Batteries have a way of gaining enough of a charge after sitting for a short while. I've left lights on in my car several times and not enough of a charge initially but if you wait a hour or so sometimes will now start. I would check that your battery is getting a good charge. Mr Holmquist is the master EFI guru.
 

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Yeah battery is brand spanking new. And I have it in trickle charger even right now to keep it fully charged. Voltage is great over 12 volts.
‘Yes I was hoping Mr Holmquist would chime in.
‘I have a feeling it’s one of the 3 things.
1) fuel pressure regulator is holding to much pressure
2 the Auto Off relay is bad. I assume this because colds starts are great after warm it will not start. So think that relay is acting up.
3)ECU is dying even though all things says it’s ready great.
 

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Have found on '92 650 that charging coil is same as in carb models. Does'nt make enough amps to keep system voltage high enough below 5000 rpm. Out put test is at 6000RPM so is misleading even if it's correct! On slow windy trail will give your symptons.
 

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Found problem guys.
‘The SSO relay was issue.
‘So when sled warmed up was not functioning correctly.
‘I took both blue relays off. Cleaned the contacts. Did military drop test on them. (Basically bangs them in wooden bench gently)
read the ohms make sure they match. Then I swapped them back into sled right to left left to right.
‘Sled is now staying running after it’s warm. All good now.
 

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Good find. Hopefully that was your issue and thanks for posting....you will likely save someone a headache at some point so long as they know what google is.
 

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Good find! Ride on - we're out of snow on the west coast so I'm going to check my relays and wait for next winter while catching a salmon or two. But I think an auxiliary marine alternator will be my repair to keep voltage in speck is necessary.
 

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Maybe you've fixed this in the meantime, but I had a similar problem with my 1995 Indy Trail Touring. What fixed it (finally) was replacing the throttle safety switch. It's located in the handlebar assembly and it's designed to kill the engine if the throttle cable sticks when you're going fast but the engine doesn't respond and slow down. If you release thumb pressure on the throttle and the cable goes slack without the engine slowing down it will kill the engine. I think over time the cable stretches causing this to happen. My machine would start right up but then would run erratically or not at all once it warmed up a bit. It seemed to run fine in warmer weather but worse in cold weather, perhaps because the cable would change its length with different temperatures.
I had the dealer diagnose and fix it but it cost around $300 (mostly labor). Good luck.
 

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Discussion Starter #15
@hobiecat
that is where I started actually. So when the issue happened I measured Ohms and volts through the TSS and it tested good.
‘Thanks for the heads up though.
 

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Mine runs long enough to get you back in the bush quits nothing will start it so you tow it back and then it starts 2nd pull Runs great tries to convince you to do it again :)
I'm about to go on a diagnostic voyage of discovery,got the computer cable,going today to get a fuel pressure guage,taking out the airbox,pulling fuel tank checking pickup,got a new battery,installing new filter,unplugging and cleaning dielectric grease plugs.
then hooking up my laptop and seeing whats up.
Then again mine sat in a garage with the cover on it for 24 years
Hopefully it doesn't need a sensor because not sure there available also
can anyone recommend a adjustable ebay fuel regulator that they have successfully used
where can I find a drop resister ?

advice on these matters welcomed

lets keep in touch
 
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