[cwlongshot]

We had some problems on Saturday...

Let me back up. My buddie bought this machine last fall. Took delivery and waited for this spring. Right off the bat he had some issues. Engine light on then off. Hard to shift, idle issues hi then lo to stalling. Took it back to dealer. They said map senser. Ordered new one. Installed and delivered back to my friend. By the end of our ride last month the problem
Resurfaced then went away. Started again as we approached camp Friday. Sat am we had to return because the machine will
Not idle.

OK spent about three hours pulling plastics
Off. Got to the senders and sensers and fuel tank. We noticed fuel pump/ junction on right side of tank loose. It only screws into plastic. Well under it we found a ground wire.
We pulled the map/ Tbap and to senser sand cleaned them. We traced som
Wires out and found that this ground is the problem. It gets/ gives intermittent ground. BIG PROBLEM FOR ELECTRONICS!

We made a better ground, the problem
Is GONE! We put over 100 miles on Sunday with zero issues. I'm betting there was no problem back when it went to dealer!

So heads up, look here before you pull your hair out. Check and fix this problem!
Its a pain pulling the front plastic. But an easy fix once off. Make a better ground. We used but and bolt to frame but more better ground is better.
CW

 

[golf12]

outstanding trouble shooting CW!.. I hated seeing post after post from guys with the 13' in particular who were being told its their map sensors that are bad when all along there's a real good chance this was the problem..

 

[mvn]

Holy SH!& CW, you are a LIFE SAVER!! I have this EXACT same issue. Random and erratic idle, hard shifting when idle is high (obviously) and intermittent TMAP code (out of range).

Can you describe where exactly this ground point is? I will check it out! Thanks a million.

Mark

 

[cwlongshot]

Glad it helps!!

CW

 

[mvn]

CW,

Is it the ground point where the 2 brown wires come from the fuel pump assembly?

Mark

 

[cwlongshot]

Holy SH!& CW, you are a LIFE SAVER!! I have this EXACT same issue. Random and erratic idle, hard shifting when idle is high (obviously) and intermittent TMAP code (out of range).

Can you describe where exactly this ground point is? I will check it out! Thanks a million.

Mark

Pull your plastics. The pull your front fender plastics. This will expose the fuel tank, on the right side is a block with hoses going in and out. Is it loose? There is a ground under it. Simply clean and tightening screw will TEMPORARILY fix. Make a permanent fix. Replace fasteners with something that all not loosen.

We made new ground to frame and left factory location as well.

CW

 

[mvn]

CW,

Thanks a lot!

Mark

 

[turboshelby]

Nice find, I'll remember to check that before replacing anymore map sensors

 

[mscldawg]

I'm confused. On the 13, did they do away with the ptf screw nut that holds the fuel pump in the tank? Was it replaced with a couple screws?


12 850EPS

 

[cwlongshot]

I'm confused. On the 13, did they do away with the ptf screw nut that holds the fuel pump in the tank? Was it replaced with a couple screws?


12 850EPS

This 2013 we had the problem with used screws into the plastic tank only... The wire was clamped between the plastic of the tank and the metal of the pump...

Sux because you cannot torque these screws at all, they strip. Piss poor design on popos part...

CW

 

[mscldawg]

Oh man that's crazy. They should have stuck with the old design. At least that didn't strip out

12 850EPS Short bus edition

 

[JimmyC]

We had some problems on Saturday...

Let me back up. My buddie bought this machine last fall. Took delivery and waited for this spring. Right off the bat he had some issues. Engine light on then off. Hard to shift, idle issues hi then lo to stalling. Took it back to dealer. They said map senser. Ordered new one. Installed and delivered back to my friend. By the end of our ride last month the problem
Resurfaced then went away. Started again as we approached camp Friday. Sat am we had to return because the machine will
Not idle.

OK spent about three hours pulling plastics
Off. Got to the senders and sensers and fuel tank. We noticed fuel pump/ junction on right side of tank loose. It only screws into plastic. Well under it we found a ground wire.
We pulled the map/ Tbap and to senser sand cleaned them. We traced som
Wires out and found that this ground is the problem. It gets/ gives intermittent ground. BIG PROBLEM FOR ELECTRONICS!

We made a better ground, the problem
Is GONE! We put over 100 miles on Sunday with zero issues. I'm betting there was no problem back when it went to dealer!

So heads up, look here before you pull your hair out. Check and fix this problem!
Its a pain pulling the front plastic. But an easy fix once off. Make a better ground. We used but and bolt to frame but more better ground is better.
CW

Great find and thank you for sharing! I'm sure you saved quite a few people some $$ and more importantly keeping their ATVs outa the shop! :beer:

 

[mvn]

The only block I see on the right side of the airbox is the ignition coil. It has a shield wire running under it and is clamped between the coil and the airbox. The IAC valve is just forward of the coil and has a connector and 2 hoses but no "pinched" ground wire. If I trace the ground wires from the fuel pump/sender, they run up to a large collection of brown ground wires that are terminated with a ring terminal. Using a nut and bolt, a 6 gauge black wire connects this mass of grounds to the BATT negative terminal. Everything there was clean and tight.

Since all of my plastics are off, I will swap out the TMAP sensor anyway.

The TMAP has 4 wires and is directly connected to the ECM.

It would be interesting to know what codes were set on CW's buddies 850 when the CEL was on.

Mark

 

[cwlongshot]

We did not have the book to read them.
His is a '13 but unknown exact build date.
I took some pics but unfortunately none of that side.



The ring terminal was pinched between the block and plastic tank. We also traced it out to the junction.

Was where any of the screws loose? It was very loose on this bike. IMHO the issue is with the screw into plastic. You simply cannot tighten it sufficiently to prevent loosening. Thread lockers do not work well on plastic.

As I mentioned, this was second time for this issue. First time it went to dealer and he waited weeks for the part. The map senser. We pulled and checked it as well as TP both where nice and clean.

That machine now has almost one hundred and eighty miles on it since the issue with no reoccurrence of the problems. To my mind it acted just like what we found.

CW

 

[mvn]

Yes, the wire you are referring to is the shield wire from the ignition module to GROUND B. I will go back and have a closer look.

I'm glad the problem seems to be fixed in your case. In my case, it happened back in the spring but has not come back. Everything so far is tight and clean. I am reseating all connectors and am using dielectric grease on all connections. I did find the stator connector not locked properly and it was intermittently disconnecting causing a low voltage condition.

Big ride coming soon so I hope I catch any deficiencies beforehand.

Mark