Jump to content

Detecting misfire on a g4x plug in 2006 Sti


Wildt267

Recommended Posts

I'm trying to troubleshoot at intermittent misfire at low load. I read a post on here indicating the factory trigger wheel lacks the resolution to be able to accurately track misfires.  On my factory ecu i was able to monitor a parameter called "roughness" which i thought was tracking misfires.   How did the factory ecu do that and is there something similar in the g4x that i haven't found yet?

Link to comment
Share on other sites

37 minutes ago, Wildt267 said:

On my factory ecu i was able to monitor a parameter called "roughness" which i thought was tracking misfires.   How did the factory ecu do that and is there something similar in the g4x that i haven't found yet?

Have you seen the Engine Speed ROC runtime value? It might work as some approximation of engine roughness.

Link to comment
Share on other sites

2 minutes ago, kaptainballistik said:

If you have the COP coils, Can you stick them into another car to try them? 

For some reason the Link can "drive" coils that on a STD ecu wont even work!

Ask me how I know this...:huh:

unfortunately not but that's a good idea.  I just replaced the coils with a new Oem set.

21 hours ago, Vaughan said:

Have you seen the Engine Speed ROC runtime value? It might work as some approximation of engine roughness.

That was an excellent idea, thank you. Sure enough i'm seeing some negative values where there shouldn't be.  Didn't catch that in the logs as i was so focused on everything else.

Link to comment
Share on other sites

16 hours ago, kaptainballistik said:

Are you getting Missfires on over 15PSi of boost?

it's more of a low load thing. Doesn't really seem to be getting them in boost 

6 hours ago, remski2 said:

Your coils.. they are 3ms or 5ms. ?

And is that reflected in the dwell table.

My dwell table goes from about 5ms dropping down to 2.8ms at high rpm.  I think i tried to increase the dwell a bit awhile back but didnt see and change so i backed them back down.

Link to comment
Share on other sites

20 hours ago, Wildt267 said:

it's more of a low load thing. Doesn't really seem to be getting them in boost 

My dwell table goes from about 5ms dropping down to 2.8ms at high rpm.  I think i tried to increase the dwell a bit awhile back but didnt see and change so i backed them back down.

That still doesnt tell us which coils you have. 

Your table setting are for 5ms coils..

Black coils are 3ms Grey coils are 5ms

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...