[JimThot]

I’m wondering if it is okay to lower the index of all 6 injectors at once. Currently a car i’m selling had index 12’s and my own summer car has index 5. so i swapped and coded the injectors between the two cars. On the car that i swapped from index 12 to 5, when i first did the swap it was misfiring on cylinder 5 so i put an index 7 injector and coded it and it seemed to fix the problem, but now as time has passed it now has a slight shakiness when idling at operating temperature only and not when it is cold. I also noticed when the shaking occurs, the rpm idles at around a stable 750 rpm instead of 550 rpm, and again only when it’s at operating temperature. When it’s cold it is completely fine, no shaking and rpm is idling at 550 rpm. Could it be because of the injectors or is it something else like a ignition coil?

[TiAgAu]

Hopefully you coded them right?

Edit: Nvm i can't read.

[Tambohamilton]

Originally Posted by TiAgAu

Hopefully you coded them right?

says he did...

No reason for this not to work, providing everything is done right. May as well try swapping coils to see if the misfire moves too.

[JimThot]

Originally Posted by Tambohamilton

says he did...

No reason for this not to work, providing everything is done right. May as well try swapping coils to see if the misfire moves too.

Originally Posted by TiAgAu

Hopefully you coded them right?

yep coded using inpa. when it was giving the misfire code i did swap the coils and it didn’t change anything. I gotta run a live data test to see which cylinder is giving trouble.
Odd thing was that before doing this swap over the car was completely fine with no shaking at all.
Also is there a reason for the increase in idle rpm? only thing i could maybe think of is maybe an adaption issue since it has different fuel rates? i’m not sure what to do

[suspect]

Originally Posted by JimThot

yep coded using inpa. when it was giving the misfire code i did swap the coils and it didn’t change anything. I gotta run a live data test to see which cylinder is giving trouble.
Odd thing was that before doing this swap over the car was completely fine with no shaking at all.
Also is there a reason for the increase in idle rpm? only thing i could maybe think of is maybe an adaption issue since it has different fuel rates? i’m not sure what to do

Is the teflon seal around the injector tip ok?

[JimThot]

Originally Posted by suspect

Is the teflon seal around the injector tip ok?

they seemed fine to me but i didnt change them

[JimThot]

Update:
TLDR: Found out cylinder 2 was misfiring so i changed injector on that cylinder as well and now i have 2 misfiring cylinders only when idling at operating temperature


I’m very confused about what’s going on now… Still having the issue of misfires when idling at operating temperature and it becomes worse when starting the car at operating temperature. Inpa said cylinder 5 was misfiring and had a lean fuel mixture so i checked the spark plug and it was fine as i replaced them not too long ago, moved the ignition coil to a different cylinder and it stayed on cylinder 5. I then replaced the injector with an extra used index 7 injector i had and it didn’t help. Today i noticed that on live data that cylinder 2 was outside its opening smoothness value and cylinder 5 was in tolerance even though my error code still said cylinder 5. So i checked the spark plug on cylinder 2 and it was also okay. I then put the same injector i had in cylinder 5 before i replaced with the index 7 and now im still having the same issue only at opening temperature but now the error codes are saying cylinder 2 and 5 are misfiring. Can someone explain whats going on?

[lowrydr310]

Seems like you should be focusing on injectors since that's the only variable if both cars were running fine before the swap. I personally wouldn't re-use injector seals especially if they have been on the car a long time. For me any time an injector gets moved or replaced it gets a new seal and decoupler ring.

Though I'm also not aware of any misfire issues from bad injector seals, unless they're really not sealing at all.

Are the electrical connectors for the injectors fully seated? Any of them have broken tabs?

This may sound stupid but are the coils seated properly and connected properly? I'm experienced working with cars but dumb me messed up a plug/coil replacement had a coil that wasn't fully pressed down onto the plug AND another coil where I didn't have the electrical connector fully engaged with the tabs on the coil and locked in place, both causing two simultaneous misfires.