Loss of power and popping - Kawasaki KFX450 Forum :: KFX450HQ.com
General Discussion Talk about anything on your mind here.

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 35 (permalink) Old 08-25-2019, 11:59 AM Thread Starter
Junior Member
 
Join Date: Aug 2019
Posts: 15
View Chapman13wired's Photo Gallery(0)
Loss of power and popping

Hey my name is Andy and I recently bought a 08 kfx 450r and it has either a wiring issue or something because it will run fine one minute and the next minute it cuts out and pops and has no power and then it will start dying out. I dont know much about wiring but it has a new battery and I have checked voltage on it. I know when I unplug the coolant temp sensor it gets worse so idk if that's the issue. Dont want to dump a bunch of money into parts it dont need. Can anyone help please
Chapman13wired is offline  
Sponsored Links
Advertisement
 
post #2 of 35 (permalink) Old 08-25-2019, 05:34 PM
Senior Member
 
Join Date: Jan 2019
Posts: 216
View Blayzin212's Photo Gallery(0)
I'm not the guy with all the answers but there are a couple here that do. It goes to a default setting when u unplug the coolant temp sensor and it will run worse.

Sent from my SAMSUNG-SM-G935A using Tapatalk
Blayzin212 is online now  
post #3 of 35 (permalink) Old 08-25-2019, 09:17 PM
Senior Member
 
blue99stroker's Avatar
 
Join Date: Jan 2014
Location: Northern California
Posts: 1,830
View blue99stroker's Photo Gallery(0)
It’s tough to diagnose the FI at times

Ground the DFI circuit and see if any codes pop up.

Could be a bad coil, failing fuel pump/relay or water temp sensor

08 KFX450r- DASA, FCI, Stage 2 Hotcams, Wiseco Programmer, Procom, Dynatek Coil, 6K HID, 7" LED Light Bar.

Race Tech dual rate front springs, GT thunder XC Link and Race tech spring

Poly Case Saver, Streamline Stabilizer, Full PRM Skidplates, Pro Armor Bumpers, Tusk Heel Guards, TRX Rear Hubs, IMS 3.7 tank
blue99stroker is offline  
Sponsored Links
Advertisement
 
post #4 of 35 (permalink) Old 08-26-2019, 04:49 PM
Senior Member
 
Join Date: Jan 2019
Posts: 216
View Blayzin212's Photo Gallery(0)
I've completely reconstructed my kfx. The main wire harness, every sensor, ecu, and every bearing and bushing. Theres a lot of wires but it's not as bad as you think it is.

Are you mechanically inclined?
If you have a manual and tools, I will give u a list of things to check.

Sent from my SAMSUNG-SM-G935A using Tapatalk
Blayzin212 is online now  
post #5 of 35 (permalink) Old 08-26-2019, 04:55 PM
Senior Member
 
Join Date: Jan 2019
Posts: 216
View Blayzin212's Photo Gallery(0)
If I had to guess... I'd go straight for the vehicle down sensor. It's under your front plastic. If your sitting on the bike it's almost dead center in front of the handlebars. It will be a 2" rectangular black box with 3 wires going in to it.
It needs to be in the correct position all of the time. I bet it's not mounted properly or it's broken and loose, and it bounces around and tries to shut you bike down

Sent from my SAMSUNG-SM-G935A using Tapatalk
Blayzin212 is online now  
post #6 of 35 (permalink) Old 08-27-2019, 10:31 AM
Super Moderator
Premium Member
 
Dust Devil's Avatar
 
Join Date: Oct 2009
Location: Lake Havasu city, Arizona
Posts: 9,451
View Dust Devil's Photo Gallery(0)
Quote:
Originally Posted by Chapman13wired View Post
Hey my name is Andy and I recently bought a 08 kfx 450r and it has either a wiring issue or something because it will run fine one minute and the next minute it cuts out and pops and has no power and then it will start dying out. I dont know much about wiring but it has a new battery and I have checked voltage on it. I know when I unplug the coolant temp sensor it gets worse so idk if that's the issue. Dont want to dump a bunch of money into parts it dont need. Can anyone help please
Welcome to the Forum...!!

Cutting out & popping is a very lean air/fuel mixture usually low fuel pressure... common is a clogged fuel pump strainer...

Is your motor all stock or with mods...List the mods if yes..?

Is your ECU stock or Procom...?

If the ECU is stock...Can you run the self diagnostic to point you in the right direction..?? see picture below...

Self diagnostic ORANGE wire is under the hood in a black pouch...Ground it to the frame...!
http://www.frewracing.com/users/boys...20190827082957
Attached Thumbnails
Click image for larger version

Name:	Self diagnosis.JPG
Views:	7
Size:	127.6 KB
ID:	24486   Click image for larger version

Name:	Self diagnostic.JPG
Views:	7
Size:	182.8 KB
ID:	24488   Click image for larger version

Name:	000_0437.JPG
Views:	8
Size:	427.6 KB
ID:	24490  

Check with Site Sponsors "First"

(Immortal ATV)
Todd
http://immortalatv.com
1-(800)380-9646
[email protected]
Save 5% off $100 or more, use coupon code: KFX450HQ

(KB Motor-sports)
Website:
http://www.kbmotorsportsonline.com

(Discount Tire)
At The Store: www.discounttire.com
To Your Door: www.discounttiredirect.com
Sales and Technical: 1.888.459.4080




Dust Devil is offline  
post #7 of 35 (permalink) Old 08-28-2019, 09:54 PM Thread Starter
Junior Member
 
Join Date: Aug 2019
Posts: 15
View Chapman13wired's Photo Gallery(0)
It is completely stock except power core 4 exhaust. I checked for codes and got nothing. I have messed with the down sensor some too. Even checked all the wiring for damages. I have a manual that I downloaded on my phone and am mechanically inclined. Haven't checked the screen on the fuel pump tho. It did sit for about 10 months. So that could be the issue. Not sure if it matters what grade of gas to run. Someone said I should run 91 but I put 87 in it. I have a volt meter or whatever it's called. Lol dont know much about wiring. Couldn't figure out how to test the down sensor but I thought it cut off the fuel and I know the fuel pump is working for sure.
Chapman13wired is offline  
post #8 of 35 (permalink) Old 08-29-2019, 01:23 AM
Super Moderator
Premium Member
 
Dust Devil's Avatar
 
Join Date: Oct 2009
Location: Lake Havasu city, Arizona
Posts: 9,451
View Dust Devil's Photo Gallery(0)
Quote:
Originally Posted by Chapman13wired View Post
It is completely stock except power core 4 exhaust. I checked for codes and got nothing. I have messed with the down sensor some too. Even checked all the wiring for damages. I have a manual that I downloaded on my phone and am mechanically inclined. Haven't checked the screen on the fuel pump tho. It did sit for about 10 months. So that could be the issue. Not sure if it matters what grade of gas to run. Someone said I should run 91 but I put 87 in it. I have a volt meter or whatever it's called. Lol dont know much about wiring. Couldn't figure out how to test the down sensor but I thought it cut off the fuel and I know the fuel pump is working for sure.
When it sat for 10 months was there fuel in it & did you drain it, then filled it with fresh gas...??

How to clean the fuel pump... https://www.kfx450hq.com/forums/engi...el-pump-2.html

Recommended 91 octane for the KFX stock 12:1 piston compression...!

To test the vehicle down sensor output voltage...see picture below...
Attached Thumbnails
Click image for larger version

Name:	vehicle down sensor test.JPG
Views:	5
Size:	139.4 KB
ID:	24492  

Check with Site Sponsors "First"

(Immortal ATV)
Todd
http://immortalatv.com
1-(800)380-9646
[email protected]
Save 5% off $100 or more, use coupon code: KFX450HQ

(KB Motor-sports)
Website:
http://www.kbmotorsportsonline.com

(Discount Tire)
At The Store: www.discounttire.com
To Your Door: www.discounttiredirect.com
Sales and Technical: 1.888.459.4080




Dust Devil is offline  
post #9 of 35 (permalink) Old 08-29-2019, 07:13 PM Thread Starter
Junior Member
 
Join Date: Aug 2019
Posts: 15
View Chapman13wired's Photo Gallery(0)
Ya I did change the gas but the guy I got it from did not and had been trying to get it to run. He got it from his brother that passed away. I will clean the fuel pump as soon as I get a day off and test the down sensor. Thank you all for being extremely helpful.
Chapman13wired is offline  
post #10 of 35 (permalink) Old 08-29-2019, 07:21 PM Thread Starter
Junior Member
 
Join Date: Aug 2019
Posts: 15
View Chapman13wired's Photo Gallery(0)
Also does anyone know what is good and bad as far as psi numbers if I do a compression check
Chapman13wired is offline  
Reply

  Lower Navigation
Go Back   Kawasaki KFX450 Forum :: KFX450HQ.com > KFX450 Headquarters > General Discussion

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki KFX450 Forum :: KFX450HQ.com 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











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 



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