[Lambobimmer]

I am FBO running E50 and I thought that these plugs might be beneficial. I gapped them to .022 using a feeler gauge and gap tool and installed them. My engine runs smoother than the OEM plugs once the engine has warmed up. However, it runs terrible on a cold start. Has anyone else experienced this? I am pretty sure that they are gapped correctly but I plan on checking them again. Any ideas.

My car ran fine with OEM plugs so I am certain that the issue is with the plugs and not injectors or coils.

[Miller335]

Same situation here.

The warmer the ambient temp is when doing this first cold start of the day the better. There was even a point in the height of summer where it would start perfectly every cold start.

[GoRomeo]

Try Chevron Injector cleaner. I had the same issue and all it took was a a bottle. Idle was smooth again even when cold. Actually I am probably due for another one as preventive maintenance. I added one about a year ago.

[3000GT MR]

Engine runs pretty rich during cold start. If your just fbo try.. 025-.024" Gap. 20+psi is the only time you really need to run. 022

[Lambobimmer]

Originally Posted by 3000GT MR

Engine runs pretty rich during cold start. If your just fbo try.. 025-.024" Gap. 20+psi is the only time you really need to run. 022

This is what I was thinking. I will open the gap a little.

Thanks

[adventr]

Same issue here on my N55. Runs like hell upon cold start.

But.......... My solution has been to just lightly keep my foot on the throttle upon cold start. It seems like if you do that, the computer bypasses its cold start procedure?
The exhaust stays much quieter, and the engine runs smooth with my foot just lightly pressing the throttle. Keep it there for 15-20seconds, and then you can let off and it idles down and runs great on its own.

[stanlalee]

Mine sounded exactly like that with the NGK plugs...then I regapped them perfectly and they still sounded like that....then I regapped them again and it still sounded like that....then I regapped them perfectly for the third time and my idle has been smooth for 10k miles. You really have to get the gap correct to smooth out the idle.

[Lambobimmer]

Originally Posted by stanlalee

Mine sounded exactly like that with the NGK plugs...then I regapped them perfectly and they still sounded like that....then I regapped them again and it still sounded like that....then I regapped them perfectly for the third time and my idle has been smooth for 10k miles. You really have to get the gap correct to smooth out the idle.

Did you leave the gap at .56mm or did you widen it?

[Stucks]

mine does the same thing. ngk 5992s gapped to .022

on cold starts, for the first 30 seconds or so, it cracks, hisses, and carries on until the idle drops and settles. then after that, it runs perfect.

[adventr]

Originally Posted by Stucks

mine does the same thing. ngk 5992s gapped to .022

on cold starts, for the first 30 seconds or so, it cracks, hisses, and carries on until the idle drops and settles. then after that, it runs perfect.

Try just lightly keeping your foot on the throttle next time you start it. I think I've read that when you do that (and the engine makes vacuum), that the computer bypasses it's standard cold start procedure.
It works for me anyway.


The computer is basically dumping a bunch of fuel in the cylinders at cold start in order to heat up the catalytic converters quicker. I have a catless downpipe, so no reason to do that on mine.

[tke344]

Originally Posted by adventr

Try just lightly keeping your foot on the throttle next time you start it. I think I've read that when you do that (and the engine makes vacuum), that the computer bypasses it's standard cold start procedure.
It works for me anyway.


The computer is basically dumping a bunch of fuel in the cylinders at cold start in order to heat up the catalytic converters quicker. I have a catless downpipe, so no reason to do that on mine.

I went with your advice from the N55 section, gapped at .025 and I have a smooth idle and haven't had spark issues that I know of. Not yet FBO but I'm running a lot of e85 and timing that gets me above 200 actual load. Still working on the tune however, I think the torque eff divisor table is screwing me up since I've programmed lower than normal AFR targets for the ethanol, seems like it's calculating torque to be much higher than actual and I end up overshooting load targets by a huge amount.

[j1gilles]

Originally Posted by Lambobimmer

I am FBO running E50 and I thought that these plugs might be beneficial. I gapped them to .022 using a feeler gauge and gap tool and installed them. My engine runs smoother than the OEM plugs once the engine has warmed up. However, it runs terrible on a cold start. Has anyone else experienced this? I am pretty sure that they are gapped correctly but I plan on checking them again. Any ideas.

My car ran fine with OEM plugs so I am certain that the issue is with the plugs and not injectors or coils.

Pretty normal for the NGK plugs esepcially if you run e85 during the open loop phase... Increase the gap a little and go from there. My car will throw some misfires during cold start sometimes but the disappear once the car idles for 30 or so seconds.

[AWD Addict]

Originally Posted by GoRomeo

Try Chevron Injector cleaner. I had the same issue and all it took was a a bottle. Idle was smooth again even when cold. Actually I am probably due for another one as preventive maintenance. I added one about a year ago.

snake oil.

[wren57]

Same issue here. Put them in about 2 weekends ago, car runs amazing with them other than the first 30 seconds of idle. Lots of misfires. Then it idles smooth and runs even smoother. Doesn't really bother me since the wastegates are rattling like hell during that time too . I did use the injector cleaner and it didn't help.

[adventr]

Originally Posted by tke344

I went with your advice from the N55 section, gapped at .025 and I have a smooth idle and haven't had spark issues that I know of. Not yet FBO but I'm running a lot of e85 and timing that gets me above 200 actual load. Still working on the tune however, I think the torque eff divisor table is screwing me up since I've programmed lower than normal AFR targets for the ethanol, seems like it's calculating torque to be much higher than actual and I end up overshooting load targets by a huge amount.

Good to know! I do plan on opening up my spark plug gap a bit next time I'm working on the car and the engine is cool. Seems like every time I go to mess with something, it's always 1000 degrees under there!