Update: i have my wideband and fuel pressure gauge installed now. AFR is in The low 11s part throttle and 11.8-11.9 at WOT. Fuel pressure stays between 55-58 at WOT and 60psi at idle. It starts to cut out around 4psi.

 

Also, before this started happening, AFR would hold steady at part throttle driving and would pull around 15in vacuum at idle. Now the afr swings from 13.8-15.2 at steady part throttle and only pulls 11in vacuum at idle.

 

I would say try other plugs like TR7 and see how it works. I've read some people had issues with plugs like yours.

Check to make sure you don't have exhaust leaks that will affect your AFR.

Did you check your valve springs? Could be weak springs causing valve float.

 

It started with tr6's. No change when i went to the br7's. No exhaust leaks pre or post turbo. I have not checked valve springs though.

 

Well talking of spark plugs those 7s are too cold IMO , try some BR6ef's gapped around .30 .
I'm also Leary of the 340 pumps , I had one but ditched it quick after I heard of issues ,

What type of fuel system do you have ? Return or Rless ?
Has the truck always missed ?

 

What was the fuel level in your tank. I justed noticed you have 340 fuel pump.

I have aeromotive 340 fuel pump too and when the level in the tank is 1/4 or below, it will cut at WOT pull. When it is 1/2 full, it will not do it.

I have run TR6 upto 15 psi with no issues. Now I have TR7 at 15psi with no problem.

 

Does it happen past a certain throttle position? What's the tc status, locked and unlocked?

 

Tc is unlocked. It started with the tr6's that were in it. I figured since im swapping plugs, i would try some 7's. I had the 6's gapped at 28. Anything over 4psi or so it will miss. Regardless of throttle position. It does it with a full tank of fuel. I hardly ever run it below 1/4 tank. This pump hasnt given me any issues as of yet. I have read of the issues with them though.

 

Tim, its a returnless system with 65lb/hr injectors and the aeromotive pump. The issue started about a month ago.

 

Do you have a Fuel Pressure gauge?