Yamaha R6 Forum: YZF-R6 Forums banner
1 - 12 of 12 Posts

·
Registered
Joined
·
21 Posts
Discussion Starter · #1 ·
I am having a serious miss fire issue with my '99. It seems to be getting progressively worse. All RPM, All temps. I ohmed the coils and the resistance between the two posts for the wiring harness was nothing, but the resistance between the posts and the bottom where it connect to the spark plug was well within normal. I have installed three new sets of plugs, cleaned the carbs, and did a compression test with all cylinders at 170 lbs. cold. Im at a loss. any help would be appreciated.
 

·
SHIFT!!
Joined
·
100 Posts
Check your battery terminals to make sure they are on tight. Clean and retighen the ground wires.

If that doesn't work, try to determine which is the problem cylinder. You can do this by disconnecting a plug wire one at a time and see if the motor runs any different. The one that makes little or no difference is probably the problem cylinder.
 

·
Registered
Joined
·
21 Posts
Discussion Starter · #6 ·
What would the battery terminals have to do with anything? It starts and stay running for as long as i wish, it just misses like a M.F. and its a brand new battery, Also, I have tested all the coils, and they all test the same, 0 primary resistance, and 9.8-9.9 ohm secondary, so unless the are all bad, which im leaning towards at this point, it is something up stream, like a pick up coil, on third set of plugs so thats not it
 

·
Banned
Joined
·
7,347 Posts
well the coils according to the service manual should have a resistance of,
.238~.322 for the primary
and 8.16~11.04. it says if they do not test at this, they are bad. seems odd that all 4 went bad at once.
maybe a spike in the electrical system did it. did you replace the rectifier recently?

I just checked one of my old ones, they test @ .600ohms on the primary. I'd say you have a coil problem.
 
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top