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General Category => Information Center => Topic started by: Emtguy on March 20, 2024, 09:08:02 PM

Title: 2021 Cforce 500s starting issue. Please help
Post by: Emtguy on March 20, 2024, 09:08:02 PM
Guys I need help. My 500s won’t start without a lot of tinkering. I will add a link I posted in FB group.
It’s def a firing issue, I changed plug and let new one rest on block while I hit green button, no fire.
I then messed and wiggled with every wire I could, bumped coil pack, checked all fuses I found and all were good.
It’ll eventually start most of the time but getting worse and harder to start.
I was checking the relays and switched some around, I put one from lights into main relay and it fired up. I don’t know if I was lucky or that was issue… I do know it’s a firing issue.
I also took kill switch apart, it looks fine.
Once I get it to crank it’ll run ok most of the time. Twice it has just died and I had to fiddle with it again to get it to start.
My local dealer won’t work on them if he didn’t sale em so I’m on my own. I bought mine from a neighbor.
I’ll try to add video and link.


https://www.facebook.com/groups/1184561478570146/permalink/2111409519218666/?mibextid=W9rl1R
Title: Re: 2021 Cforce 500s starting issue. Please help
Post by: NMKawierider on March 21, 2024, 09:14:06 AM
It could be so many different things..but historically the first thing that needs checked is the engine speed sensor..aka crank position sensor. Remove, clean and inspect as outlined in the service manual.
Title: Re: 2021 Cforce 500s starting issue. Please help
Post by: Emtguy on March 21, 2024, 04:58:17 PM
It could be so many different things..but historically the first thing that needs checked is the engine speed sensor..aka crank position sensor. Remove, clean and inspect as outlined in the service manual.

It’ll eventually crank. I know when it does this it’s a fire issue because I took spark plug out and put it against block and no fire.
When it does work I can do same and see fire jump to block.
Would speed sensor cause it not to fire ?
Title: Re: 2021 Cforce 500s starting issue. Please help
Post by: NMKawierider on March 21, 2024, 06:34:22 PM
It could be so many different things..but historically the first thing that needs checked is the engine speed sensor..aka crank position sensor. Remove, clean and inspect as outlined in the service manual.

It’ll eventually crank. I know when it does this it’s a fire issue because I took spark plug out and put it against block and no fire.
When it does work I can do same and see fire jump to block.
Would speed sensor cause it not to fire ?
Engine speed sensor (not vehicle speed sensor) tells the ECU when to set the mapping for the injectors to fire and the coils. If it doesn't get good data..it won't do either....and that means no running. Pull it and see if there is any trash on the tip and test it's resistance.You might could flip it over to Tach and see if it works correctly..ie smoothly with no jumps or odd behavior like stopping sometimes or blanking out. 
Title: Re: 2021 Cforce 500s starting issue. Please help
Post by: Emtguy on March 21, 2024, 07:24:55 PM
It could be so many different things..but historically the first thing that needs checked is the engine speed sensor..aka crank position sensor. Remove, clean and inspect as outlined in the service manual.

It’ll eventually crank. I know when it does this it’s a fire issue because I took spark plug out and put it against block and no fire.
When it does work I can do same and see fire jump to block.
Would speed sensor cause it not to fire ?
It could be so many different things..but historically the first thing that needs checked is the engine speed sensor..aka crank position sensor. Remove, clean and inspect as outlined in the service manual.

It’ll eventually crank. I know when it does this it’s a fire issue because I took spark plug out and put it against block and no fire.
When it does work I can do same and see fire jump to block.
Would speed sensor cause it not to fire ?
Engine speed sensor (not vehicle speed sensor) tells the ECU when to set the mapping for the injectors to fire and the coils. If it doesn't get good data..it won't do either....and that means no running. Pull it and see if there is any trash on the tip and test it's resistance.You might could flip it over to Tach and see if it works correctly..ie smoothly with no jumps or odd behavior like stopping sometimes or blanking out. 

You mean when it’s running right, when I’m driving make sure to look at the rpm’s and see if any issues with it jumping or blanking out?

I posted a vid of me trying to start it I thought 🤘