[Scott66]

My 2010 800XP starts and runs fine. The problem is that it begins running rough after idling for a short time - the longer it idles the rougher it gets. Running it at a high RPM after idling seems to clear it up and it runs fine, including acceleration. It's almost like it 'loads up' at idle, but how/why would fuel injection do that?

I've cleaned the air cleaner and added fuel additive to clear any water in the fuel. Again, it appears to accelerate and operate okay at normal speeds.

I bought a full pressure tester, however, it won't work on the Polaris fuel line fittings.

Anybody run into this issue or have advice on what's going on and how to fix it?

Thanks,
Scott

 

[Jungleman]

Scott, really need to know what that fuel pressure is ....

Check the throttle body adapter for cracking where it bolts on to the head. Most of the time you can just 'lean' on it a little bit and the crack will show itself.

The TBAP & TPS harness should be checked for chaffing and broken wire. They like to break a wire or two where they enter the connector or rub through anywhere. If it has never been changed,it is bad..

Check for stored EFI codes >>>> Trans in neutral............rotate key three times to the "ON' (not start) position, leaving it in the ON position on the third rotation..............Wait.........two digit codes will appear if there are any. 61 is END OF CODES...

 

[AtRange007]

Go to harbor freight and get their fuel pressure tester. It has the adapter need to screw onto the line.

 

[BPS]

Go to harbor freight and get their fuel pressure tester. It has the adapter need to screw onto the line.

There's nothing to screw on to on the 800 fuel rail. They skipped over the 800s on that dandy feature.

Most kits come with a "T" that if you cap one side and put a hose on the other you can put it on the nipple on top of the fuel pump.

 

[Jungleman]

Line TEE..... https://www.amazon.com/Actron-CP783...4&sprefix=actron+fuel+pressure,aps,670&sr=8-5

 

[AtRange007]

There's nothing to screw on to on the 800 fuel rail. They skipped over the 800s on that dandy feature.

Most kits come with a "T" that if you cap one side and put a hose on the other you can put it on the nipple on top of the fuel pump.

Wonder if you could swap a fuel rail over from a 700 to fix that problem?

 

[BPS]

I just measured and they do look like they are the same spacing, height, etc. The 800s have a damper on the end as do all of the more modern rails. Not sure if that would make a difference.

 

[Scott66]

Scott, really need to know what that fuel pressure is ....

Check the throttle body adapter for cracking where it bolts on to the head. Most of the time you can just 'lean' on it a little bit and the crack will show itself.

The TBAP & TPS harness should be checked for chaffing and broken wire. They like to break a wire or two where they enter the connector or rub through anywhere. If it has never been changed,it is bad..

Check for stored EFI codes >>>> Trans in neutral............rotate key three times to the "ON' (not start) position, leaving it in the ON position on the third rotation..............Wait.........two digit codes will appear if there are any. 61 is END OF CODES...

Thanks. I wasn't aware I could access the fault codes.

 

[Scott66]

There's nothing to screw on to on the 800 fuel rail. They skipped over the 800s on that dandy feature.

Most kits come with a "T" that if you cap one side and put a hose on the other you can put it on the nipple on top of the fuel pump.

Got it. Thanks

 

[Scott66]

Thanks for the suggestions. I will get back with what I discovered later in the week.

 

[Splotch6911]

Definitely do a fuel pressure test. I went through the same issues then finally bought a tester from Harbor freight. Pressure was low and we rebuilt the fuel pump. That Polaris ran like a beast afterwards.