Koso A/F gauge doesn't always start up.....why?

[likkerpig]

I've got a Koso A/F gauge on an 06 M7, power is tapped into the Red wire going into the fuel pump, grounded to one of the bolts in the bulkhead. Started the sled up in the garage after the install, worked just fine. Finally get a chance to go ride this afternoon, start sled up, NOTHING. Does not power on. Ride for a while, stop, turn sled off, start up a few minutes later and it works just fine. Turn off sled, start back up...nothing.

Any ideas why it doesn't consistently start upon sled start up?

 

[brian_moreau7]

Mine was doing the EXACT same thing........ I had to wire a small 12v switch into mine to get it to turn on all the time.... Works great now and works all the time!

 

[m8magicandmystery]

do you have the heat sink..??...anyway i have my power on a switch..and i flip the switch on after sled heats up..after a short search of reading to high etc it works great..and if any problems i can just flip switch on or off instead of starting and shutting off sled...but so far (cross my fingers)..its working awesome...i think you may have a ground issue or poor connection etc

 

[likkerpig]

Yep, heat sink is on it. How did you wire the switch into the power and where did you put it? Any special switch or anything?

Just seems odd to me that it doesn't work EVERY time you start your sled up when it SHOULD.....

 

[m8magicandmystery]

i used just a 2 position toggle switch with a rubber toggle boot and mounted it close to key...you just have to interrupt your koso wire that is going to the fuel pump wire...is your heat sink lined up facing the flow properly...!!!..the little dot on heat sink faces the flow.....and as a last resort some people have had really good luck without the heat sink...you could try that..??

 

[likkerpig]

Yep, made sure the dot was facing the right way when I installed the bungs.

 

[m8magicandmystery]

is the 06 fuel pump dc for certian..or could it be ac...??...just a wild card cause i know they change etc...??..but should never have worked the first place

 

[m8magicandmystery]

try grounding to the engine instead of the bulkhead

 

[likkerpig]

06, from what I understand has 2 good places to tap into good DC power. 1 is right off the voltage regulator, the other is the fuel pump wire. Couldn't easily reach the voltage regulator so went with the fuel pump wire.

Edit: I'll try out the engine ground tomorrow- didn't think it would matter much but suppose it could.

 

[m8magicandmystery]

yep try that ground on the engine...all the power is created in the engine stator...the engine electrical has best ground on the engine..to many times the ground from chassis to engine is problematic...thats why lights etc run grounds back..

 

[likkerpig]

Semi-unrelated question- why does boondocker require a chassis ground and NOT an engine ground? Just curious....

 

[m8magicandmystery]

Semi-unrelated question- why does boondocker require a chassis ground and NOT an engine ground? Just curious....

don;t know...i do know they are paranoid about static issues...thet even recommend mouting there box where the snowmobile cover should not touch the box when removing it because of possible static..so maybe the chassis ground to reduce possible static issues..??..i do know that they do have alot of ground related problems by the posts i have read...just guessing here...

 

[cles]

I'm starting to wonder if the KOSO is just cheap junk. Mine did the same thing last year. The dealer gave me a new one off the shelf this fall, and it's doing the same thing. It only turns on once every two or three starts.

 

[Headrush]

What year sleds are people having issues on?

 

[likkerpig]

OK, where's a GOOD engine ground location on an 06 M7?

 

[Cosarguy]

Ran a Koso on my 08 M-1000 last year and had this same issue. Sometimes i had to shut off and restart my sled several times before the darn thing would read right....a real pain. I talked to some knowledgeable folks running and selling the Koso O2 gauge who told me, "you get used to it after a few rides." I didn't! This year I have the AEM O2 gauge and so far it has worked great.

This is a known common problem with the Koso O2 on a non battery sled. Koso EGT seems to work well though.

 

[Headrush]

Is the AEM waterproof though? I heard they aren't.....

 

[Cosarguy]

I ran silicon around where the wiring enters the gauge and have not had any issues regarding water getting into the workings of the gauge. Also, the cover can be easily removed and wiped out if needed. Mine hasn't needed it yet. Beyond that, I'm not sure how "water proof" the AEM gauges are. Maybe you need to stay out of those creek bottoms.

 

[Headrush]

^^

Only spent 5 hours in one last year with my Apex - that's one of the main reasons I'm back on a Cat!

Have you had any issues with your AEM?

 

[Cosarguy]

^^

Only spent 5 hours in one last year with my Apex - that's one of the main reasons I'm back on a Cat!

Have you had any issues with your AEM?

Not so far. Seems to read changes very fast. When my engine is cold and with the turbo on it, the motor likes to start and then go lean at least one time before settling down to business. When it does this, the AEM gauge will begin to show lean readings, 17 to 1 or leaner, then off the scale before the engine actually dies from being too lean. In other words, the gauge shows what is going on before the engine reacts.