Another missfire sympthom

[1jzr32]

Hi All,
My 1jz was run fine if light throttle till 6500rpm BUT if sudden WOT it's missfire from 4000rpm till 6500rpm.
It's confirm will be happen IF WOT & 4000rpm onwards. Any idea is much appriciate. Thanks in advance

 

[tissimo]

Do a search there are many miss fire threads.

But gap you plugs down first see if it helps, its probably that or cracked coilpacks.

 

[1jzr32]

Other than plug gap & coil crack, any possible causes...example Fuel presure?
At this moment I'm not using the FPR just direct from Nissan R32GTR fuel pump.

 

[tissimo]

Other than plug gap & coil crack, any possible causes...example Fuel presure?
At this moment I'm not using the FPR just direct from Nissan R32GTR fuel pump.

fpr is on the return..

start with the simple common problems first. once you've eliminated those then move on.

 

[1jzr32]

I will recheck the plug gap & try to wrap the coil.

 

[1jzr32]

Last nite I check all the coil , wrap the steam , Plug gap at 0.028 BUT still the same.
Should I focus on fuel presure ( Install the FPR & set to 40 psi at `off-boost').
I found it's hard to crancking atleast 3 times cranking to turn on the engine & once the engine on fuel smell at rear exhaust for few second.
Any input is much appreciate

 

[HommerSimpson]

guess no codes ?

 

[1jzr32]

yeap.. no fault code

 

[Jostar]

You on stock ECu???? IF yes then that might be the problem, they go bad, Capacitors go bad & shit starts happening.