06 Sportsman 700 EFI - Bad Fuel Pump or ECU Going Out? - Polaris ATV Forum
Polaris Sportsman Discussions for the Polaris Sportsman 90, 300, 355, 400, 450, 500, 550, 600, 700, 800, 850

 
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 09-04-2019, 07:04 PM Thread Starter
Junior Member
 
FishinFreaks's Avatar
 
Join Date: Aug 2019
Posts: 16
06 Sportsman 700 EFI - Bad Fuel Pump or ECU Going Out?

Was riding my wheeler for a couple hours. No problems. Later that afternoon, my son is riding for 5 minutes and it dies. We tow it back. We can get it to start but won't run. We can hear the fuel injectors run when we turn the key, but it still won't run much more than sputtering for 10 seconds or so. Let it sit till the next day, and it starts and runs as normal. Troubleshooting with a local mechanic where we were, he thought it is the fuel pump going out. I take it to my mechanic now that I'm home. I had a new fuel pump. He says he'll replace it but thinks it may be the ECU, rather than the fuel pump. If it was the ECU, would it even turn over?

I want to go riding out of town in a couple weeks but don't really have a way to ride locally to see if I can get it to duplicate the problem. Thoughts?
FishinFreaks is offline  
Sponsored Links
Advertisement
 
post #2 of 4 (permalink) Old 09-05-2019, 04:02 AM
Premium Member
 
bp405's Avatar
 
Join Date: Sep 2011
Location: New York
Posts: 7,233
Personally I would have tested fuel pressure as to diagnose the fule pump. The ECU doesn't control fuel pressure. So testing pump pressure narrows things down.

2011 Sportsman® 800 EFI
GURU front brush guard
GURU rear brush guard
Polaris front lock n ride cargo box
Polaris rear rack extender
Warn RT 3.0 winch w/amsteel synthetic line
Viper aluminum haus fairlead
Polaris front spring adjusters
Ricochet a-arm guards
Ricochet full frame skid plate
ITP T-7 beadlock 14" w/OMF inner rim guards
Maxxis big horn 2.0 26x9 front
Maxxis big horn 2.0 26x11 rear
QSC clutch kit
EPI HD springs front n rear
ODI rogue 130mm grips
Ultraseal commercial grade tire sealant (front)
Highlifter tire sealant (rear)
CTEK 3300 battery maintainer
added 7 zerks
beefed up wiring harness
OGIO rear bag
ROTOPAX 1gal. + 2gal. gasoline can
Jccapri bushing kit
Kolpin Over Fenders
Rigid Industries E-Series 10" flood
Walker Evans struts
NGK Iridium's (2,500 miles on Champion's and they looked great!)
Odyssey Extreme battery PC545

2018 Sportsman® 570-T
2019 Aluma® A8818
2020 Outlander® 1000R XXC
bp405 is online now  
post #3 of 4 (permalink) Old 09-05-2019, 05:49 AM
Moderator
 
polman500's Avatar
 
Join Date: Nov 2009
Location: SE Kentucky
Posts: 8,550
From what you describe I'm guessing that...
1) the air temperature was HOT
2) the machine was HOT
3) the tank was only half full of low octane alcohol blended corn juice instead of REAL gas
5) the tank and fuel lines have very little or no heat shielding
6) the exhaust header directly under the tank has no wrap or heat shielding on it
7) the pump is beginning to get weak from all of the above
When it was acting up you could probably have "fixed" it, at least temporarily, by pouring the tank full of good cool fuel.

You can't do anything much about items 1 & 2. But I suspect if you correct most or all of items 3-7 you probably won't have any more issues like that.
1) Get the new pump installed asap.
2) While the tank is already off to put the pump in, cover the tank bottom and wrap the fuel line with good heatshield matting that can be found at most auto parts stores. I'm talking about heatshield matting, NOT the little thin tin foil stuff Polaris uses!
3) Fill the tank with good quality non-alcohol real gas.

Wrapping the exhaust will also help but is not as important as the other three things.
I could be wrong but I doubt there's anything wrong with the ECU.
Let us know how it works out.
polman500 is online now  
Sponsored Links
Advertisement
 
post #4 of 4 (permalink) Old 09-05-2019, 07:21 AM Thread Starter
Junior Member
 
FishinFreaks's Avatar
 
Join Date: Aug 2019
Posts: 16
Thanks for the below suggestions. One thing I didn't note below is that I only run non-ethanol gas in it.

Air temperature was only around 80, so not terribly hot.

I had my guy replace the fuel pump yesterday. I guess I'll just go ride and see what happens?

Quote:
Originally Posted by polman500 View Post
From what you describe I'm guessing that...
1) the air temperature was HOT
2) the machine was HOT
3) the tank was only half full of low octane alcohol blended corn juice instead of REAL gas
5) the tank and fuel lines have very little or no heat shielding
6) the exhaust header directly under the tank has no wrap or heat shielding on it
7) the pump is beginning to get weak from all of the above
When it was acting up you could probably have "fixed" it, at least temporarily, by pouring the tank full of good cool fuel.

You can't do anything much about items 1 & 2. But I suspect if you correct most or all of items 3-7 you probably won't have any more issues like that.
1) Get the new pump installed asap.
2) While the tank is already off to put the pump in, cover the tank bottom and wrap the fuel line with good heatshield matting that can be found at most auto parts stores. I'm talking about heatshield matting, NOT the little thin tin foil stuff Polaris uses!
3) Fill the tank with good quality non-alcohol real gas.

Wrapping the exhaust will also help but is not as important as the other three things.
I could be wrong but I doubt there's anything wrong with the ECU.
Let us know how it works out.
FishinFreaks is offline  
Reply

  Lower Navigation
Go Back   Polaris ATV Forum > Polaris Model Specific Discussions > Polaris Sportsman

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Polaris ATV Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome