Coolant Temp Sensor resistance values

Discussion in 'EFI/carb' started by HUSKYnXJnWI, Aug 2, 2010.

  1. HUSKYnXJnWI Husqvarna
    AA Class

    Location:
    Central Wisconsin, USA
    Husqvarna Motorcycle:
    09TE450
  2. Coffee CH Owner

    Location:
    Between homes - in ft Wayne IN
    Husqvarna Motorcycle:
    2006 TE250, 2013 TR650 Terra - sold
    I put a copy in the tech ref forum here :)
  3. michael Husqvarna
    C Class

    would this be a possible cause to the problem im having?


    i belive it has something to do with heat but not acctually over heating? first off i have a 09 husky sm450r, it has power up kit on with the cats removed out of factory exhaust, and a high flow race water pump, other than that its all factory.
    now the proplem is after riding it for long distances its looses power. originally it was after about the 20-30 min mark of continues riding.(on the hwy) i figured it was overheating and going into i guess a fail safe mode? so i put the race water pump and engine ice, as well as rapped the exhaust with heat rap. well that def made a diffrence but only moved the time limit to were it would do it again to 30-45mins. i have not got it tuned in anyway and i looked at the plug and its not running lean, (by the way the plug looks).. i just cant figure this out?
    i mean the bike runs fine, starts fine. when it happens its like someone flips a switch and the bike has half to 3/4 power? I got mad this weekend at it and put it in 2nd gear was going about 15mph pulled the clutch in, banged it off revlimiter and dumpped the clutch! The wheel came up about 6 inchs and went back down and went on about its bussness.
    If i ever did that when it was running correctly it would fly out from under me with a snap of the finger!!! I know something is not rite here? I raced another 09 sm450r that had everything same as mine except he was runing the cats on his exhaust, and he would pull from me when the problem would start to happen.
    I love the bike but it kills me when it does this! i was going to buy the power surge 6 from JD jettings to see if tunning it would fix it? and then i was thinking that there is something wrong with my ECU? i just dont know anymore?
    any help on what to look at/test would be great
  4. HUSKYnXJnWI Husqvarna
    AA Class

    Location:
    Central Wisconsin, USA
    Husqvarna Motorcycle:
    09TE450
    Yes- you should check out the temp sensor-and/ or replace. If the bike is HOT and it thinks its COLD it it throws things off badly- and a JD tuner or PC -w/autotune cannot fix that- you could chase it but not fix it. I'd test it if you have a meter, before simply swaping for a new temp sensor: moreso to verify- but the temp sensors are about $10 so its no big deal either way. 10$ is cheaper than any tuner and may directly address the cause to your problem.

    ALSO/ if you are using a one way valve on your gas cap- (stock one is about the worst/ since its so stout) it can create a vacume and or pressure and stress your pump and pressure. I just mention this because right now- heat/and riding time causes your problem as just as pausing for 20 minutes fixxes your problem- so this could equally be an issue. I use a straight hose for this reason.
  5. columbia510 Husqvarna
    AA Class

    Location:
    columbia,ca
    My 450te was running bad when warm. Then it would just run bad all the time. It would backfire,fart,snort, and cough under 4000rpm then launch like her bum was on fire over 4000rpm. I didn't have I-beat so I drove to Motoxotica(awesome service) and they discovered the temp sensor was bad and I had a intermittent bad fuel pump. I have been happy ever since.
  6. michael Husqvarna
    C Class

    okay thanks man, ill def give that a try? thats the first helpful info ive got on this issue... :applause: i have changed the hose on the fuel cap but it does have a one way valve on it. to let air in but not out.. ill def change that to a striaght hose. were can i get the temp sensor at? is it a universal sensor or does it have to be from husky?
    thanks again. ill repost the out come of my problem to say weather everything fixed the problem or not.
  7. michael Husqvarna
    C Class

    okay so i just tested the sensor.... i rode it into work so i let the bike sit to cool down just enough for me to touch the motor safely.. it is about 55 degrees outside here rite now. i unpluged the sensor and tested the ohms on it, and i put a laser thermostate on the head. at 76 degrees (outside head temp) the sensor read 1429 ohms and was slowly going up as the motor cooled down. i then reatached the plug to sensor and cranked up the bike let it warm for about 5 min. and then re connected the ohm meter to sensor. and at 120 degree (outside head temp) the sensor read 668 ohms.. so im thinkng that the temp sensor is def falty? please correct me if im wrong on this...
  8. HUSKYnXJnWI Husqvarna
    AA Class

    Location:
    Central Wisconsin, USA
    Husqvarna Motorcycle:
    09TE450
    Part Number
    DescriptionQuantityPriceItem Total
    8000H3649 SENSOR, WATER TEMPERATURE $14.50 $14.50

    Looks like Halls Husqvarna has them and they'll ship it to you as well.
    Here a recent thread asking where to buy- most places should have them or access listed-

    It probably cross refferances with some other part used on something else but that hasn't been researched that I know of partly because they are readily available and not over priced... I'd just get the OEM part... they have been updated since more than enough of them have failed. I am still using mine original from my 09TE450 so go figure.:thinking: Guess I am lucky
  9. michael Husqvarna
    C Class

    thanks man . i just ordered one from them. ive been posting on supermoto junkies about this problem for the past 2 months and NO one would reply.. cant wait to get the new sensor to get this think fixed up..
  10. HUSKYnXJnWI Husqvarna
    AA Class

    Location:
    Central Wisconsin, USA
    Husqvarna Motorcycle:
    09TE450
    Good- and yes looking at your numbers:
    1429ohms cold to my 690ohms cold/ and 668ohms hot to my 162ohms hot
    You are decreasing resistance with heat (normal)- BUT your numbers are so out of spec (high) that your bike thinks its cold all the time (my cold versus your hot). Will run RICH when hot. Also I bet your fan never came on. If you tried to unplug your temp sensor when hot- it wouldn't have helped in this case... YES this is a problem that would cause your symtoms.

    When you get your new one- I'd test cold resistance and verify that your fan comes on after idling for awhile then test hot resistances.

    :thumbsup:good luck,
  11. little squirt Husqvarna
    AA Class

    Location:
    Honolulu, HI
    so unplugging the temp sensor when hot, to see if the bike runs any different is possible? I think im going to try this after work just for giggles... So in a way the computer is fueling the bike based on engine temp and not what the 02 sensor is telling it? or does it just favor the engine temp in regards to the fuel curve?
  12. michael Husqvarna
    C Class

    no the bike will not run with the sensor unplugged.. (at least mine didnt) i tryed it and it wouldnt start and the display on the instrament cluster said FAIL... i belive if your having the hot no start problem you can unplug the sensor and plug it back in to trick the computer for a min to get it to start when hot...???
  13. michael Husqvarna
    C Class

    okay man, i dont think its the temp sensor? i just got the BRAND NEW one in the mail. i tested it rite out of the box and it reads. 1.865 ohms its 73 degrees in my house.. i went and pulled the old sensor out of my bike and let it sit in the house for a min to get adjusted to the temp in my house. when i tested the old one it read almost the exact same thing! not understanding why a brand new sensor is reading the same thing out of the bike? im going to install the new one anyways but now im really confused? any help on explainen this situation. i wouldnt think the new one is bad rite out of the box?
  14. JasonfromMN Husqvarna
    AA Class

    Location:
    MN
    Husqvarna Motorcycle:
    None right now :(
    Other Motorcycles:
    2013 Yamaha FZ6R
    Is it possible it will only read a faulty ohms when warm? I'd try that before you rule it out.
  15. michael Husqvarna
    C Class

    Yeah was going to try that today, as a budy here at work told me the same thing.. ill post back and give update after test.
  16. HUSKYnXJnWI Husqvarna
    AA Class

    Location:
    Central Wisconsin, USA
    Husqvarna Motorcycle:
    09TE450
    Ultimately the best test is hooking up to Ibeat- The ohm readings should not be different than mine- it should have the same operating range. So other than getting another bad one- I too would be confused.
  17. michael Husqvarna
    C Class

    also i was just comparing numbers from what HUSKYnXJnWI put originally.. my readings were way off compared to his? his cold reading was (690 ohms cold at 82 degrees) my new sensor was reading (1.865 ohms at 73 degrees)? i guess the sensor could drop 688 ohms in 10 degrees? thats the diffrence from my readin and temp from HUSKYnXJnWI's...
  18. sami Husqvarna
    C Class

    Location:
    finland
    hello

    my sensor was reading
    17´C 2,745 kohm
    35 1,267
    36,6 1,150
    39 1,08
    53 0,58
    56 0,456

    is the sensor ok?
  19. pluro Husqvarna
    B Class

    Location:
    wv
    I've been struggling with an overheating '10 TE 310 for a year now: new temperature sensor, hi output water pump, engine ice, cutout radiator guard to not block fan, and most recently by passed the temp sensor so I can just turn the fan manually when it's hot out or I'm in the tight stuff: It's still overheating.
    Thinking about hier pressure radiator cap (1.4 stock ) and waterless coolant
  20. HUSKYnXJnWI Husqvarna
    AA Class

    Location:
    Central Wisconsin, USA
    Husqvarna Motorcycle:
    09TE450
    The Coolant Temp Sensor gives the ecu information for fueling adjustments and fan operation. (really does not have a direct relationsip to causing the bike to overheat (other than its contribution to fueling adjustments (rich/lean).
    Some bikes- TE-xlites: also have a Thermostat in line with the coolant hoses. This helps maintain opperating temps for more consistant fueling- it is often not needed in "race" conditions. It can fail and stick open or closed causing issues. Sticking open would be better than closed.
    The Radiator Cap- determines when coolant is released by how much pressure is behind it. This is a wear item as well as can be "upgraded" to different levels of pressure. I believe stock is 1.2 bar. Yours may be weak or not sealing properly- causing coolant to "PUKE" early rather than "boiling over"- either way going to a higher bar will cause it to increase the boiling point as well as the "puking" pressure point.

    If you bypassed your Temp Sensor- depending on how you did it your bike could be running lean and adding to the overheating issue- definately going to effect how well the bike runs. I'd reconnect this back to stock form if you this is what you did. Look at your Radiator Cap for replacement, or the thermostat for replacement or elimination.