Switchback low idle.. no reverse

[plumloco]

My '05 Swtichback 900 ran beauty the other day then after about 3 hrs it started to idle very low..low enough to stall out. The PERC stopped working also at this time.
I tried to bring the idle up with throttle lever to get the reverse to work but that didnt work.
Since it idles that low.. no gauges or lights work... if I throttle it up a little (to 1100;1200rpm), they do come back on though.

One other note, when you start the sled for the 1st time for the day, no gauges or lights work until the sled warms up then they are good for the rest of the day.

Any help is greatly appreciated as the is a nice blanket of new snow out there today...

 

[hearse driver]

Hey my 900 did the same thing a couple weeks ago- turned out to be the Tps sensor. Watch when you set it though they are real sensitive. Oh ya I'd checkout the intake adapters from throttle body's to the engine- mine were cracked up bad and is common problem,lots of related info in 900 forum on this site - good luck!

 

[plumloco]

Hey, hearse driver...Thanks so much for the reply...I'm hoping since you had that trouble, mine is the same fix.
Looked it up on-line and I'll have to buy a TPS tester..or make one.
Hopefully, I can get at it soon and get back to you on the results... I'll look at those intake boots also.
This site is great

 

[plumloco]

Ok.. got up this morning built a TPS sensor tester (as seen on the internet).. seems to work as I hooked it up and got a reading of .92 at idle... manual calls for .93 but I left it there.
Checked the intake adaptors which also look good (no cracks).
Started the sled and all seemed great and even the reverse worked perfect... then once the sled warmed up more, the idle dropped back down and reverse doesn't work again....even if I throttle it up to about 1400rpm.
I'm open to any other ideas...pleeeease.... before the local shop gets another $600-$700 .

 

[fnDan]

Did you check the TPS with the idle set screw backed all the way off?
My RMK is supposed to be .709 - .711.
There's a procedure for resting the throttle body baseline in the manual.

 

[plumloco]

Thanks mac900rmk... since it was so close to idle spec .93 +/- .02... I just left it but I will check with idle screw backed off today.

 

[hearse driver]

apparently there was a problem with the wires goin to the tps also. They were crap wires that would break so maybe check that as well when your in there, but if all the updates were done at the dealer they should have changed that harness.

 

[plumloco]

Lastest damn update goes like this... Caliberated the TPS as described in the manual... .710 with idle screw backed off....930 with idle screw in.
I did do an ohms check thru all 3 wires of the TPS shook the hell out of them and no problem.
Checked all wiring and put electrical ties on all connections while the the tank was off.... started it up and everything seems perfect.. reverse even works... then after 5 minutes or so you hear the idle drop down almost to the point of stalling.. and reverse button does nothing

I'd like to thank all for the advice... think my next step is the local Polaris dealer

 

[hdkawi]

what's your compresion if it's to low your reverse wil not work check it cold then hot if it's low put some 2 stroke oil in it and check it again if it goes up
it's your rings if it doesnt change it's your reeds

 

[plumloco]

Thanks for the info....I have not checked the compression but will this week... and reply back.
I really was thinking something electrical or electronic but really don't know.
I did check and cleaned all electrical connections.. including grounds.
my 1st post mentioned the gauges and lights didn't work on the 1st start of the day (for about 5 min).. after cleaning all grounds and connections that issue is gone. We thought the low idle and perc issue were solved too,, my boy took it out and everything seemed good but when he pulled up and got off it to open the back fence the idle dropped and the perc stopped working.

 

[plumloco]

Thought I'd send a reply/update... It seems as thought the low idle/ no PERC trouble was the TPS. i have set it a few different times but the problem would show up after a couple hours of running.
last time it happened i pulled the plug off the TPS and the idle raised.. decided to just replace the TPS after that and after setting it up as the manual recommended the trouble has disappeared. My boy has had 3 good rides.. without any trouble.
I'd like to thank everyone for the advice.

 

[powder junkie]

The tps on 900 r super sensitive. Will cause most headaches. Glad u got it fixed