Sportsman 700 efi sputtering and stalling
 

2005 Sportsman 700 efi

Started sputtering and occasionally will stall.

I'll be driving around and it will get boggy, if I stop and come to an idle it will either low idle around 800 rpm or it will simply stall out. If it stalls out, I will start it and it will run fine immediately after. If it doesn't stall out the low idle will eventually clear itself within a few seconds. I can drive around fine for a bit then it will do it again. I have a flat 2 acre yard so I'm not working it hard. No warning lights showing on the display.

Things I've checked or done:
I have a fuel psi gage attached and when it sputters or stalls the psi remains around 38 psi
I checked the tps and it is at .710 dcv at idle
Pulled the plugs and they are golden brown
Fresh gas


Need help on what to do next??

Look over this "sticky" post on 700/800 efi problems.https://atvconnection.com/forums/pol...ap-wiring.html It explains about the thin wiring and also the manual states that efi problems are 80% wiring related,not a problem with sensors themselves. It may or may not throw codes when this happens,but does sound like what happens with the t bap wiring harness or connector. Erratic idle,stalling,back firing is just some of the symptoms. You can look for any visible bare wires from the t bap sensor and also feel for any soft internally melted wires and the connector itself for any pins that may have pulled back a little. Polaris "repair kits" listed for these are junk! This you can trust me on because I replaced many over and over again. If it's a wiring problems,then this place has a lot better harness repair kits than Polaris has. First repair kit listed.Only The Best

Thanks old tech, wasnt sure cause codes arent showing up. I ordered the recommended connector, hopefully it fixes my issues.

Most of the time I never had codes show up when it was a t bap wiring problem. Hope the otb repair kit solves the problem. Keep us updated.

I had the same problem with my 2005 70EFI .. It was the wiring harness as explained by the tech.. Resolved my issue.

I've got about 30 minutes on the new tbap wring so far and no issues. I'm cautiously optimistic that this fixed the problem. When I took the old one off someone else had either replaced with the Polaris kit or repaired the wiring of the original. I didn't see anything obvious when I cut the old one out.

Either one is a good enough reason why it failed. Either someones' rigging on the wiring or a crappy Polaris harness kit. Hopefully the better harness and connector solves the problem permanently for you.

I took my 700 out today, first time since my last post and it started doing it again. Its colder out 22deg out. Can tps affect this? I remember last year when I first moved the tps it was at .700vdc instead of .710. Currently I put it at .710, could this be affecting this?

First off any time you mess with the tps setting you're asking for trouble if you screw up the internal tps spring! IF you have the correct harness adapter,along with the voltage regulator and a 9 volts battery you can try to set the tps at the correct base line of .528 vdc,BUT the throttle cable has to have slack removed from the buttery fly wheel first.Then you need to have the special "D" ring driver for the throttle body idle adjuster to remove tension from the butterfly valve completely! Once that's done the base line vdc can be set and the tps tightened down. Then you adjust the idle screw with the d ring driver to 710 vdc.If you just adjusted the tps sensor to get to 710 vdc,you've screwed up..You might have to take this to the dealer or if you have the harness,you can try to adjust it correctly. Hopefully the tps sensor wont have to be replaced..

Could this cause my symptoms?

Entirely possible, but check the wiring from the tps connector that goes into the main harness. If you find any bare or soft feeling wire there you might be able to fix it and get by without having to resort to having a new tps installed. Not sure if otb has a harness kit for this tps,but if you find that the problem is in the wiring,give them a shout. Only The Best

Thanks OPT
You have always been very responsive and resourceful to my posts.

I found online how to set the baseline and then adjust the idle screw from there to achieve the final tps reading. Just have to get the D shaped tool to adjust the idle screw.

http://www.polarisatvforums.com/foru...fi-models.html

Remember first take all cable pressure off the throttle body wheel,then turn the adjuster until it doesn't touch the butterfly valve. Then loosen the tps screws and set the base line to .528 vdc. I'd cross my fingers for you,but I can't.. :)

Well
Disconnected the throttle cable and took the idle screw all the way out. Adjusted tps to .528 on the nuts. Put in idle screw and turned until I hit .710. Fired up machine and still get an undershoot. If I rev it, let off the throttle it will sometimes undershoot by about 100-150 rpm so that it idles around 1000 rpm, then on its own it will come back to 1150-1200. Verified fuel pressure is at 40psi. I'm really starting to hate this machine.

If you haven't cleaned the throttle body out with electrical contact cleaner especially around the butterfly and the shaft,you might try that and see if it helps,could be sticking. If no change then the idle drop could be from the spring inside the tps sensor when you first readjusted the tps. Doesn't take much to damage this sensor.Plus double check the throttle cable to make sure you have a little slack(1/8") on the thumb lever and the cable isn't binding leading to the throttle body. You also might try adjusting the throttle body adjuster up a tad say to .715 vdc and see how it does.Worst case scenario would be to replace the high dollar tps sensor and start from scratch. Both it and the throttle body have updated part numbers,but new part #'s don't always indicate a major change in the parts. Item#10. Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse Average rpm I usually had when set right was 1150-1180.

I cleaned the throttle while I was in there, it wasn't bad, I did it last year as preventative. I verified cable has about 1/8" play. I think I have another used tps I can try.

Can I do these to verify tps or tbap sensor/wiring?
1. Hook my meter up to the tps and see if the idle vdc is repeating or if they are fluctuating while machine is running.
2. Unhook the tps or tbap and see if issue still exists. Shouldn't the machine throw a code but go into a safety/default mode? If issue goes away its related to that sensor or sensors wiring. Or will this not work?

Hook the harness back up to the tps and you can recheck that the voltage is smooth and doesn't jump as you slowly raise and lower the butterfly. If it does,the tps spring could be messed up. Found that quite a bit when people messed with tps settings. If the voltage drops and rises smoothly on the tps then check the connector and wiring leading down into the main harness. It can have the same faulty connector and wiring as the tbap can. You might even check continuity on the connector pins and wiring right before the leads go into the main harness to make sure.